diff --git a/sys/arduino/base.cpp b/sys/arduino/base.cpp
index 65f6a450c0..41df7b7534 100644
--- a/sys/arduino/base.cpp
+++ b/sys/arduino/base.cpp
@@ -26,7 +26,7 @@ extern "C" {
 
 #include "arduino.hpp"
 
-#define ANALOG_PIN_NUMOF     (sizeof(arduino_analog_map) / sizeof(arduino_analog_map[0]))
+#define ANALOG_PIN_NUMOF     (ARRAY_SIZE(arduino_analog_map))
 
 void pinMode(int pin, int mode)
 {
diff --git a/sys/auto_init/can/auto_init_can_native.c b/sys/auto_init/can/auto_init_can_native.c
index 320ed576be..ac70361901 100644
--- a/sys/auto_init/can/auto_init_can_native.c
+++ b/sys/auto_init/can/auto_init_can_native.c
@@ -20,7 +20,7 @@
 #include "can/device.h"
 #include "candev_linux_params.h"
 
-#define CANDEV_LINUX_NUMOF ((sizeof(candev_linux_params) / sizeof(candev_params_t)))
+#define CANDEV_LINUX_NUMOF ARRAY_SIZE(candev_linux_params)
 
 #ifndef CANDEV_LINUX_STACKSIZE
 #define CANDEV_LINUX_STACKSIZE (THREAD_STACKSIZE_DEFAULT + THREAD_EXTRA_STACKSIZE_PRINTF)
diff --git a/sys/auto_init/can/auto_init_periph_can.c b/sys/auto_init/can/auto_init_periph_can.c
index 5f30c9f068..0b361ffa20 100644
--- a/sys/auto_init/can/auto_init_periph_can.c
+++ b/sys/auto_init/can/auto_init_periph_can.c
@@ -20,7 +20,7 @@
 #include "can/device.h"
 #include "can_params.h"
 
-#define CANDEV_NUMOF ((sizeof(candev_params) / sizeof(candev_params[0])))
+#define CANDEV_NUMOF (ARRAY_SIZE(candev_params))
 
 #ifndef CANDEV_STACKSIZE
 #define CANDEV_STACKSIZE (THREAD_STACKSIZE_DEFAULT + THREAD_EXTRA_STACKSIZE_PRINTF)
diff --git a/sys/auto_init/netif/auto_init_at86rf2xx.c b/sys/auto_init/netif/auto_init_at86rf2xx.c
index 256733b9e7..88b0767290 100644
--- a/sys/auto_init/netif/auto_init_at86rf2xx.c
+++ b/sys/auto_init/netif/auto_init_at86rf2xx.c
@@ -42,7 +42,7 @@
 #define AT86RF2XX_MAC_PRIO          (GNRC_NETIF_PRIO)
 #endif
 
-#define AT86RF2XX_NUM (sizeof(at86rf2xx_params) / sizeof(at86rf2xx_params[0]))
+#define AT86RF2XX_NUM ARRAY_SIZE(at86rf2xx_params)
 
 static at86rf2xx_t at86rf2xx_devs[AT86RF2XX_NUM];
 static char _at86rf2xx_stacks[AT86RF2XX_NUM][AT86RF2XX_MAC_STACKSIZE];
diff --git a/sys/auto_init/netif/auto_init_cc110x.c b/sys/auto_init/netif/auto_init_cc110x.c
index 3378600474..7a0e9df67e 100644
--- a/sys/auto_init/netif/auto_init_cc110x.c
+++ b/sys/auto_init/netif/auto_init_cc110x.c
@@ -38,7 +38,7 @@
 #define CC110X_MAC_PRIO          (GNRC_NETIF_PRIO)
 #endif
 
-#define CC110X_NUM (sizeof(cc110x_params)/sizeof(cc110x_params[0]))
+#define CC110X_NUM ARRAY_SIZE(cc110x_params)
 
 static netdev_cc110x_t cc110x_devs[CC110X_NUM];
 static char _stacks[CC110X_NUM][CC110X_MAC_STACKSIZE];
diff --git a/sys/auto_init/netif/auto_init_cc2420.c b/sys/auto_init/netif/auto_init_cc2420.c
index b37f687172..a53287a0a5 100644
--- a/sys/auto_init/netif/auto_init_cc2420.c
+++ b/sys/auto_init/netif/auto_init_cc2420.c
@@ -42,7 +42,7 @@
 /**
  * @brief   Get the number of configured CC2420 devices
  */
-#define CC2420_NUMOF        (sizeof(cc2420_params) / sizeof(cc2420_params[0]))
+#define CC2420_NUMOF        ARRAY_SIZE(cc2420_params)
 
 /**
  * @brief   Allocate memory for dev descriptors, stacks, and 802.15.4 adaption
diff --git a/sys/auto_init/netif/auto_init_enc28j60.c b/sys/auto_init/netif/auto_init_enc28j60.c
index 0e8c00d280..878984697e 100644
--- a/sys/auto_init/netif/auto_init_enc28j60.c
+++ b/sys/auto_init/netif/auto_init_enc28j60.c
@@ -39,7 +39,7 @@
 /**
  * @brief   Find out how many of these devices we need to care for
  */
-#define ENC28J60_NUM    (sizeof(enc28j60_params) / sizeof(enc28j60_params[0]))
+#define ENC28J60_NUM    ARRAY_SIZE(enc28j60_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
diff --git a/sys/auto_init/netif/auto_init_kw2xrf.c b/sys/auto_init/netif/auto_init_kw2xrf.c
index adbbc5f23e..83c79296b4 100644
--- a/sys/auto_init/netif/auto_init_kw2xrf.c
+++ b/sys/auto_init/netif/auto_init_kw2xrf.c
@@ -39,7 +39,7 @@
 #define KW2XRF_MAC_PRIO          (GNRC_NETIF_PRIO)
 #endif
 
-#define KW2XRF_NUM (sizeof(kw2xrf_params)/sizeof(kw2xrf_params[0]))
+#define KW2XRF_NUM ARRAY_SIZE(kw2xrf_params)
 
 static kw2xrf_t kw2xrf_devs[KW2XRF_NUM];
 static char _kw2xrf_stacks[KW2XRF_NUM][KW2XRF_MAC_STACKSIZE];
diff --git a/sys/auto_init/netif/auto_init_mrf24j40.c b/sys/auto_init/netif/auto_init_mrf24j40.c
index 32d22fd01e..1bd5176d84 100644
--- a/sys/auto_init/netif/auto_init_mrf24j40.c
+++ b/sys/auto_init/netif/auto_init_mrf24j40.c
@@ -36,7 +36,7 @@
 #define MRF24J40_MAC_PRIO          (GNRC_NETIF_PRIO)
 #endif
 
-#define MRF24J40_NUM (sizeof(mrf24j40_params) / sizeof(mrf24j40_params[0]))
+#define MRF24J40_NUM ARRAY_SIZE(mrf24j40_params)
 
 static mrf24j40_t mrf24j40_devs[MRF24J40_NUM];
 static char _mrf24j40_stacks[MRF24J40_NUM][MRF24J40_MAC_STACKSIZE];
diff --git a/sys/auto_init/netif/auto_init_slipdev.c b/sys/auto_init/netif/auto_init_slipdev.c
index 4d743d832c..0e019d6be0 100644
--- a/sys/auto_init/netif/auto_init_slipdev.c
+++ b/sys/auto_init/netif/auto_init_slipdev.c
@@ -27,7 +27,7 @@
 #include "slipdev.h"
 #include "slipdev_params.h"
 
-#define SLIPDEV_NUM (sizeof(slipdev_params)/sizeof(slipdev_params_t))
+#define SLIPDEV_NUM ARRAY_SIZE(slipdev_params)
 
 /**
  * @brief   Define stack parameters for the MAC layer thread
diff --git a/sys/auto_init/netif/auto_init_sx127x.c b/sys/auto_init/netif/auto_init_sx127x.c
index f3c97a39c5..d6fffebc17 100644
--- a/sys/auto_init/netif/auto_init_sx127x.c
+++ b/sys/auto_init/netif/auto_init_sx127x.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Calculate the number of configured SX127x devices
  */
-#define SX127X_NUMOF        (sizeof(sx127x_params) / sizeof(sx127x_params_t))
+#define SX127X_NUMOF        ARRAY_SIZE(sx127x_params)
 
 /**
  * @brief   Define stack parameters for the MAC layer thread
diff --git a/sys/auto_init/netif/auto_init_w5100.c b/sys/auto_init/netif/auto_init_w5100.c
index efb550b6c0..0fdcdd2b51 100644
--- a/sys/auto_init/netif/auto_init_w5100.c
+++ b/sys/auto_init/netif/auto_init_w5100.c
@@ -35,7 +35,7 @@
 /**
  * @brief   Find out how many of these devices we need to care for
  */
-#define W5100_NUM    (sizeof(w5100_params) / sizeof(w5100_params[0]))
+#define W5100_NUM    ARRAY_SIZE(w5100_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
diff --git a/sys/auto_init/netif/auto_init_xbee.c b/sys/auto_init/netif/auto_init_xbee.c
index 3c64e2654a..fc52a9c1b3 100644
--- a/sys/auto_init/netif/auto_init_xbee.c
+++ b/sys/auto_init/netif/auto_init_xbee.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Calculate the number of configured XBee devices
  */
-#define XBEE_NUM        (sizeof(xbee_params) / sizeof(xbee_params_t))
+#define XBEE_NUM        ARRAY_SIZE(xbee_params)
 
 /**
  * @brief   Define stack parameters for the MAC layer thread
diff --git a/sys/auto_init/saul/auto_init_ad7746.c b/sys/auto_init/saul/auto_init_ad7746.c
index 9295107f7e..faffea0132 100644
--- a/sys/auto_init/saul/auto_init_ad7746.c
+++ b/sys/auto_init/saul/auto_init_ad7746.c
@@ -31,7 +31,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define AD7746_NUM   (sizeof(ad7746_params) / sizeof(ad7746_params[0]))
+#define AD7746_NUM   ARRAY_SIZE(ad7746_params)
 
 /**
  * @brief   Allocate memory for the device descriptors.
@@ -47,7 +47,7 @@ static saul_reg_t saul_entries[AD7746_NUM * 3];
 /**
  * @brief   Define the number of saul info
  */
-#define AD7746_INFO_NUM (sizeof(ad7746_saul_info) / sizeof(ad7746_saul_info[0]))
+#define AD7746_INFO_NUM ARRAY_SIZE(ad7746_saul_info)
 
 /**
  * @brief   Reference the driver structs
diff --git a/sys/auto_init/saul/auto_init_adc.c b/sys/auto_init/saul/auto_init_adc.c
index 9bdfcf784c..3aa86cf976 100644
--- a/sys/auto_init/saul/auto_init_adc.c
+++ b/sys/auto_init/saul/auto_init_adc.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define SAUL_ADC_NUMOF    (sizeof(saul_adc_params)/sizeof(saul_adc_params[0]))
+#define SAUL_ADC_NUMOF    ARRAY_SIZE(saul_adc_params)
 
 /**
  * @brief   Allocate memory for pointers to the ADC parameter structs
diff --git a/sys/auto_init/saul/auto_init_adcxx1c.c b/sys/auto_init/saul/auto_init_adcxx1c.c
index fa46cbad01..c0c12d7caf 100644
--- a/sys/auto_init/saul/auto_init_adcxx1c.c
+++ b/sys/auto_init/saul/auto_init_adcxx1c.c
@@ -31,7 +31,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define ADCXX1C_NUM   (sizeof(adcxx1c_params) / sizeof(adcxx1c_params[0]))
+#define ADCXX1C_NUM   ARRAY_SIZE(adcxx1c_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -46,7 +46,7 @@ static saul_reg_t saul_entries[ADCXX1C_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define ADCXX1C_INFO_NUM (sizeof(adcxx1c_saul_info) / sizeof(adcxx1c_saul_info[0]))
+#define ADCXX1C_INFO_NUM ARRAY_SIZE(adcxx1c_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_ads101x.c b/sys/auto_init/saul/auto_init_ads101x.c
index 4291fc3791..3e72e51650 100644
--- a/sys/auto_init/saul/auto_init_ads101x.c
+++ b/sys/auto_init/saul/auto_init_ads101x.c
@@ -33,7 +33,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define ADS101X_NUM   (sizeof(ads101x_params) / sizeof(ads101x_params[0]))
+#define ADS101X_NUM   ARRAY_SIZE(ads101x_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -48,7 +48,7 @@ static saul_reg_t saul_entries[ADS101X_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define ADS101X_INFO_NUM (sizeof(ads101x_saul_info) / sizeof(ads101x_saul_info[0]))
+#define ADS101X_INFO_NUM ARRAY_SIZE(ads101x_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_adxl345.c b/sys/auto_init/saul/auto_init_adxl345.c
index 46c0d4e3f9..d7df15cd7b 100644
--- a/sys/auto_init/saul/auto_init_adxl345.c
+++ b/sys/auto_init/saul/auto_init_adxl345.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define ADXL345_NUM    (sizeof(adxl345_params) / sizeof(adxl345_params[0]))
+#define ADXL345_NUM    ARRAY_SIZE(adxl345_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[ADXL345_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define ADXL345_INFO_NUM (sizeof(adxl345_saul_info) / sizeof(adxl345_saul_info[0]))
+#define ADXL345_INFO_NUM ARRAY_SIZE(adxl345_saul_info)
 
 /**
  * @brief   Reference the driver structs
diff --git a/sys/auto_init/saul/auto_init_bmp180.c b/sys/auto_init/saul/auto_init_bmp180.c
index 0245b2a75b..be87446902 100644
--- a/sys/auto_init/saul/auto_init_bmp180.c
+++ b/sys/auto_init/saul/auto_init_bmp180.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define BMP180_NUM      (sizeof(bmp180_params) / sizeof(bmp180_params[0]))
+#define BMP180_NUM      ARRAY_SIZE(bmp180_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -44,7 +44,7 @@ static saul_reg_t saul_entries[BMP180_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define BMP180_INFO_NUM (sizeof(bmp180_saul_info) / sizeof(bmp180_saul_info[0]))
+#define BMP180_INFO_NUM ARRAY_SIZE(bmp180_saul_info)
 
 /**
  * @name    Reference the driver structs.
diff --git a/sys/auto_init/saul/auto_init_bmx055.c b/sys/auto_init/saul/auto_init_bmx055.c
index 02c4f65f68..053660919a 100644
--- a/sys/auto_init/saul/auto_init_bmx055.c
+++ b/sys/auto_init/saul/auto_init_bmx055.c
@@ -28,7 +28,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define BMX055_NUM          (sizeof(bmx055_params) / sizeof(bmx055_params[0]))
+#define BMX055_NUM          ARRAY_SIZE(bmx055_params)
 
 /**
  * @brief   Each sensor contains 3 individual i2c modules
diff --git a/sys/auto_init/saul/auto_init_ccs811.c b/sys/auto_init/saul/auto_init_ccs811.c
index f6d922225a..a587e248fe 100644
--- a/sys/auto_init/saul/auto_init_ccs811.c
+++ b/sys/auto_init/saul/auto_init_ccs811.c
@@ -25,7 +25,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define CCS811_NUM      (sizeof(ccs811_params) / sizeof(ccs811_params[0]))
+#define CCS811_NUM      ARRAY_SIZE(ccs811_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -40,7 +40,7 @@ static saul_reg_t saul_entries[CCS811_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define CCS811_INFO_NUM (sizeof(ccs811_saul_info) / sizeof(ccs811_saul_info[0]))
+#define CCS811_INFO_NUM ARRAY_SIZE(ccs811_saul_info)
 
 /**
  * @name    Reference the driver structs.
diff --git a/sys/auto_init/saul/auto_init_dht.c b/sys/auto_init/saul/auto_init_dht.c
index 2be6677229..dbdc3ba5d4 100644
--- a/sys/auto_init/saul/auto_init_dht.c
+++ b/sys/auto_init/saul/auto_init_dht.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define DHT_NUM     (sizeof(dht_params) / sizeof(dht_params[0]))
+#define DHT_NUM     ARRAY_SIZE(dht_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[DHT_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define DHT_INFO_NUM (sizeof(dht_saul_info) / sizeof(dht_saul_info[0]))
+#define DHT_INFO_NUM ARRAY_SIZE(dht_saul_info)
 
 /**
  * @name    Import SAUL endpoints
diff --git a/sys/auto_init/saul/auto_init_ds18.c b/sys/auto_init/saul/auto_init_ds18.c
index a40dbeb4d0..3265f7a635 100644
--- a/sys/auto_init/saul/auto_init_ds18.c
+++ b/sys/auto_init/saul/auto_init_ds18.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define DS18_NUMOF    (sizeof(ds18_params) / sizeof(ds18_params[0]))
+#define DS18_NUMOF    ARRAY_SIZE(ds18_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
diff --git a/sys/auto_init/saul/auto_init_ds75lx.c b/sys/auto_init/saul/auto_init_ds75lx.c
index e80e273a9c..a70f05a49d 100644
--- a/sys/auto_init/saul/auto_init_ds75lx.c
+++ b/sys/auto_init/saul/auto_init_ds75lx.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define DS75LX_NUM      (sizeof(ds75lx_params) / sizeof(ds75lx_params[0]))
+#define DS75LX_NUM      ARRAY_SIZE(ds75lx_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -44,7 +44,7 @@ static saul_reg_t saul_entries[DS75LX_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define DS75LX_INFO_NUM (sizeof(ds75lx_saul_info) / sizeof(ds75lx_saul_info[0]))
+#define DS75LX_INFO_NUM ARRAY_SIZE(ds75lx_saul_info)
 
 /**
  * @name    Reference the driver structs.
diff --git a/sys/auto_init/saul/auto_init_fxos8700.c b/sys/auto_init/saul/auto_init_fxos8700.c
index bbcaa1bc3c..35b600c5d9 100644
--- a/sys/auto_init/saul/auto_init_fxos8700.c
+++ b/sys/auto_init/saul/auto_init_fxos8700.c
@@ -28,7 +28,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define FXOS8700_NUM    (sizeof(fxos8700_params)/sizeof(fxos8700_params[0]))
+#define FXOS8700_NUM    ARRAY_SIZE(fxos8700_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
diff --git a/sys/auto_init/saul/auto_init_gpio.c b/sys/auto_init/saul/auto_init_gpio.c
index 0047986462..817cf06679 100644
--- a/sys/auto_init/saul/auto_init_gpio.c
+++ b/sys/auto_init/saul/auto_init_gpio.c
@@ -26,6 +26,7 @@
 #include "saul/periph.h"
 #include "gpio_params.h"
 #include "periph/gpio.h"
+#include "kernel_defines.h"
 
 /**
  * @brief   Define the number of configured sensors
@@ -37,7 +38,7 @@ void auto_init_gpio(void)
     LOG_DEBUG("[auto_init_saul] no SAUL GPIO configured!\n");
 }
 #else
-#define SAUL_GPIO_NUMOF (sizeof(saul_gpio_params)/sizeof(saul_gpio_params[0]))
+#define SAUL_GPIO_NUMOF ARRAY_SIZE(saul_gpio_params)
 
 
 /**
diff --git a/sys/auto_init/saul/auto_init_grove_ledbar.c b/sys/auto_init/saul/auto_init_grove_ledbar.c
index 198454bdca..34359aa721 100644
--- a/sys/auto_init/saul/auto_init_grove_ledbar.c
+++ b/sys/auto_init/saul/auto_init_grove_ledbar.c
@@ -31,7 +31,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define GROVE_LEDBAR_NUM     (sizeof(grove_ledbar_params) / sizeof(grove_ledbar_params[0]))
+#define GROVE_LEDBAR_NUM     ARRAY_SIZE(grove_ledbar_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -46,7 +46,7 @@ static saul_reg_t saul_entries[GROVE_LEDBAR_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define GROVE_LEDBAR_INFO_NUM (sizeof(grove_ledbar_saul_info) / sizeof(grove_ledbar_saul_info[0]))
+#define GROVE_LEDBAR_INFO_NUM ARRAY_SIZE(grove_ledbar_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_hdc1000.c b/sys/auto_init/saul/auto_init_hdc1000.c
index bb443d586a..8f7ea7ae50 100644
--- a/sys/auto_init/saul/auto_init_hdc1000.c
+++ b/sys/auto_init/saul/auto_init_hdc1000.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define HDC1000_NUM    (sizeof(hdc1000_params) / sizeof(hdc1000_params[0]))
+#define HDC1000_NUM    ARRAY_SIZE(hdc1000_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[HDC1000_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define HDC1000_INFO_NUM    (sizeof(hdc1000_saul_info) / sizeof(hdc1000_saul_info[0]))
+#define HDC1000_INFO_NUM    ARRAY_SIZE(hdc1000_saul_info)
 
 /**
  * @name    Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_hts221.c b/sys/auto_init/saul/auto_init_hts221.c
index 119820593a..6648b593b0 100644
--- a/sys/auto_init/saul/auto_init_hts221.c
+++ b/sys/auto_init/saul/auto_init_hts221.c
@@ -30,9 +30,9 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define HTS221_NUM      (sizeof(hts221_params)/sizeof(hts221_params[0]))
+#define HTS221_NUM      ARRAY_SIZE(hts221_params)
 
-#define HTS221_SAUL_NUM (sizeof(hts221_saul_info)/sizeof(hts221_saul_info[0]))
+#define HTS221_SAUL_NUM ARRAY_SIZE(hts221_saul_info)
 /**
  * @brief   Allocate memory for the device descriptors
  */
diff --git a/sys/auto_init/saul/auto_init_io1_xplained.c b/sys/auto_init/saul/auto_init_io1_xplained.c
index 51aede77bb..eca0aa82a3 100644
--- a/sys/auto_init/saul/auto_init_io1_xplained.c
+++ b/sys/auto_init/saul/auto_init_io1_xplained.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define IO1_XPLAINED_NUM    (sizeof(io1_xplained_params) / sizeof(io1_xplained_params[0]))
+#define IO1_XPLAINED_NUM    ARRAY_SIZE(io1_xplained_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -44,7 +44,7 @@ static saul_reg_t saul_entries[IO1_XPLAINED_NUM * 4];
 /**
  * @brief   Define the number of saul info
  */
-#define IO1_XPLAINED_INFO_NUM    (sizeof(io1_xplained_saul_info) / sizeof(io1_xplained_saul_info[0]))
+#define IO1_XPLAINED_INFO_NUM    ARRAY_SIZE(io1_xplained_saul_info)
 
 /**
  * @name    Reference the driver structs.
@@ -74,7 +74,7 @@ void auto_init_io1_xplained(void)
 
         /* GPIOs */
         for (unsigned j = 0;
-             j < sizeof(io1_xplained_saul_gpios) / sizeof(io1_xplained_saul_gpios[0]);
+             j < ARRAY_SIZE(io1_xplained_saul_gpios);
              j++) {
             saul_reg_t *entry = &saul_entries[i * 4 + j + 1];
             entry->dev = &(io1_xplained_saul_gpios[j]);
diff --git a/sys/auto_init/saul/auto_init_isl29020.c b/sys/auto_init/saul/auto_init_isl29020.c
index d2203da2eb..0bcb9629a0 100644
--- a/sys/auto_init/saul/auto_init_isl29020.c
+++ b/sys/auto_init/saul/auto_init_isl29020.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define ISL29020_NUM    (sizeof(isl29020_params) / sizeof(isl29020_params[0]))
+#define ISL29020_NUM    ARRAY_SIZE(isl29020_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[ISL29020_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define ISL29020_INFO_NUM    (sizeof(isl29020_saul_info) / sizeof(isl29020_saul_info[0]))
+#define ISL29020_INFO_NUM    ARRAY_SIZE(isl29020_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_jc42.c b/sys/auto_init/saul/auto_init_jc42.c
index f00c706132..e57a52d940 100644
--- a/sys/auto_init/saul/auto_init_jc42.c
+++ b/sys/auto_init/saul/auto_init_jc42.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define JC42_NUM      (sizeof(jc42_params) / sizeof(jc42_params[0]))
+#define JC42_NUM      ARRAY_SIZE(jc42_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -44,7 +44,7 @@ static saul_reg_t saul_entries[JC42_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define JC42_INFO_NUM    (sizeof(jc42_saul_info) / sizeof(jc42_saul_info[0]))
+#define JC42_INFO_NUM    ARRAY_SIZE(jc42_saul_info)
 
 /**
  * @brief   Reference the driver structs.
diff --git a/sys/auto_init/saul/auto_init_l3g4200d.c b/sys/auto_init/saul/auto_init_l3g4200d.c
index 0e90cfca8a..89a32f3602 100644
--- a/sys/auto_init/saul/auto_init_l3g4200d.c
+++ b/sys/auto_init/saul/auto_init_l3g4200d.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define L3G4200D_NUM    (sizeof(l3g4200d_params) / sizeof(l3g4200d_params[0]))
+#define L3G4200D_NUM    ARRAY_SIZE(l3g4200d_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[L3G4200D_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define L3G4200D_INFO_NUM    (sizeof(l3g4200d_saul_info) / sizeof(l3g4200d_saul_info[0]))
+#define L3G4200D_INFO_NUM    ARRAY_SIZE(l3g4200d_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_lis2dh12.c b/sys/auto_init/saul/auto_init_lis2dh12.c
index 789e54075a..702dabb5a7 100644
--- a/sys/auto_init/saul/auto_init_lis2dh12.c
+++ b/sys/auto_init/saul/auto_init_lis2dh12.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Number of configured sensors
  */
-#define LIS2DH12_NUM    (sizeof(lis2dh12_params) / sizeof(lis2dh12_params[0]))
+#define LIS2DH12_NUM    ARRAY_SIZE(lis2dh12_params)
 
 
 /**
diff --git a/sys/auto_init/saul/auto_init_lis3dh.c b/sys/auto_init/saul/auto_init_lis3dh.c
index 813880bf1b..726cac862b 100644
--- a/sys/auto_init/saul/auto_init_lis3dh.c
+++ b/sys/auto_init/saul/auto_init_lis3dh.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define LIS3DH_NUM    (sizeof(lis3dh_params) / sizeof(lis3dh_params[0]))
+#define LIS3DH_NUM    ARRAY_SIZE(lis3dh_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[LIS3DH_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define LIS3DH_INFO_NUM    (sizeof(lis3dh_saul_info) / sizeof(lis3dh_saul_info[0]))
+#define LIS3DH_INFO_NUM    ARRAY_SIZE(lis3dh_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_lis3mdl.c b/sys/auto_init/saul/auto_init_lis3mdl.c
index bf1f76f0c3..009692cf4b 100644
--- a/sys/auto_init/saul/auto_init_lis3mdl.c
+++ b/sys/auto_init/saul/auto_init_lis3mdl.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define LIS3MDL_NUM    (sizeof(lis3mdl_params)/sizeof(lis3mdl_params[0]))
+#define LIS3MDL_NUM    ARRAY_SIZE(lis3mdl_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[LIS3MDL_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define LIS3MDL_INFO_NUM    (sizeof(lis3mdl_saul_info)/sizeof(lis3mdl_saul_info[0]))
+#define LIS3MDL_INFO_NUM    ARRAY_SIZE(lis3mdl_saul_info)
 
 /**
  * @brief   Reference the driver structs
diff --git a/sys/auto_init/saul/auto_init_lpsxxx.c b/sys/auto_init/saul/auto_init_lpsxxx.c
index 5a190cff48..63bef7d6bb 100644
--- a/sys/auto_init/saul/auto_init_lpsxxx.c
+++ b/sys/auto_init/saul/auto_init_lpsxxx.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define LPSXXX_NUM      (sizeof(lpsxxx_params) / sizeof(lpsxxx_params[0]))
+#define LPSXXX_NUM      ARRAY_SIZE(lpsxxx_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[LPSXXX_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define LPSXXX_INFO_NUM    (sizeof(lpsxxx_saul_info) / sizeof(lpsxxx_saul_info[0]))
+#define LPSXXX_INFO_NUM    ARRAY_SIZE(lpsxxx_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_lsm303dlhc.c b/sys/auto_init/saul/auto_init_lsm303dlhc.c
index 4eea707995..07b32b2c41 100644
--- a/sys/auto_init/saul/auto_init_lsm303dlhc.c
+++ b/sys/auto_init/saul/auto_init_lsm303dlhc.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define LSM303DLHC_NUM    (sizeof(lsm303dlhc_params) / sizeof(lsm303dlhc_params[0]))
+#define LSM303DLHC_NUM    ARRAY_SIZE(lsm303dlhc_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[LSM303DLHC_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define LSM303DLHC_INFO_NUM    (sizeof(lsm303dlhc_saul_info) / sizeof(lsm303dlhc_saul_info[0]))
+#define LSM303DLHC_INFO_NUM    ARRAY_SIZE(lsm303dlhc_saul_info)
 
 /**
  * @name    Reference the driver structs
diff --git a/sys/auto_init/saul/auto_init_lsm6dsl.c b/sys/auto_init/saul/auto_init_lsm6dsl.c
index b6e2969204..eaffa30e72 100644
--- a/sys/auto_init/saul/auto_init_lsm6dsl.c
+++ b/sys/auto_init/saul/auto_init_lsm6dsl.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define LSM6DSL_NUM    (sizeof(lsm6dsl_params) / sizeof(lsm6dsl_params[0]))
+#define LSM6DSL_NUM    ARRAY_SIZE(lsm6dsl_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[LSM6DSL_NUM * 3];
 /**
  * @brief   Define the number of saul info
  */
-#define LSM6DSL_INFO_NUM    (sizeof(lsm6dsl_saul_info) / sizeof(lsm6dsl_saul_info[0]))
+#define LSM6DSL_INFO_NUM    ARRAY_SIZE(lsm6dsl_saul_info)
 
 /**
  * @name    Reference the driver structs
diff --git a/sys/auto_init/saul/auto_init_ltc4150.c b/sys/auto_init/saul/auto_init_ltc4150.c
index 4d967a8e72..c5a6c7df81 100644
--- a/sys/auto_init/saul/auto_init_ltc4150.c
+++ b/sys/auto_init/saul/auto_init_ltc4150.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define LTC4150_NUM     (sizeof(ltc4150_params) / sizeof(ltc4150_params[0]))
+#define LTC4150_NUM     ARRAY_SIZE(ltc4150_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[LTC4150_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define LTC4150_INFO_NUM (sizeof(ltc4150_saul_info) / sizeof(ltc4150_saul_info[0]))
+#define LTC4150_INFO_NUM ARRAY_SIZE(ltc4150_saul_info)
 
 /**
  * @name    Import SAUL endpoints
diff --git a/sys/auto_init/saul/auto_init_mag3110.c b/sys/auto_init/saul/auto_init_mag3110.c
index 5874e68f8b..8557aebcf7 100644
--- a/sys/auto_init/saul/auto_init_mag3110.c
+++ b/sys/auto_init/saul/auto_init_mag3110.c
@@ -31,7 +31,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define MAG3110_NUM     (sizeof(mag3110_params) / sizeof(mag3110_params[0]))
+#define MAG3110_NUM     ARRAY_SIZE(mag3110_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -46,7 +46,7 @@ static saul_reg_t saul_entries[MAG3110_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define MAG3110_INFO_NUM    (sizeof(mag3110_saul_info) / sizeof(mag3110_saul_info[0]))
+#define MAG3110_INFO_NUM    ARRAY_SIZE(mag3110_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_mma7660.c b/sys/auto_init/saul/auto_init_mma7660.c
index f4d220b8ef..b2ba62b62d 100644
--- a/sys/auto_init/saul/auto_init_mma7660.c
+++ b/sys/auto_init/saul/auto_init_mma7660.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define MMA7660_NUM       (sizeof(mma7660_params) / sizeof(mma7660_params[0]))
+#define MMA7660_NUM       ARRAY_SIZE(mma7660_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[MMA7660_NUM];
 /**
  * @brief   Define the number of configured sensors
  */
-#define MMA7660_INFO_NUM  (sizeof(mma7660_saul_info) / sizeof(mma7660_saul_info[0]))
+#define MMA7660_INFO_NUM  ARRAY_SIZE(mma7660_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_mma8x5x.c b/sys/auto_init/saul/auto_init_mma8x5x.c
index 4dcc0344c4..b1c37aca00 100644
--- a/sys/auto_init/saul/auto_init_mma8x5x.c
+++ b/sys/auto_init/saul/auto_init_mma8x5x.c
@@ -31,7 +31,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define MMA8X5X_NUM     (sizeof(mma8x5x_params) / sizeof(mma8x5x_params[0]))
+#define MMA8X5X_NUM     ARRAY_SIZE(mma8x5x_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -46,7 +46,7 @@ static saul_reg_t saul_entries[MMA8X5X_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define MMA8X5X_INFO_NUM    (sizeof(mma8x5x_saul_info) / sizeof(mma8x5x_saul_info[0]))
+#define MMA8X5X_INFO_NUM    ARRAY_SIZE(mma8x5x_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_mpl3115a2.c b/sys/auto_init/saul/auto_init_mpl3115a2.c
index ea113530bd..b3baf1eb4e 100644
--- a/sys/auto_init/saul/auto_init_mpl3115a2.c
+++ b/sys/auto_init/saul/auto_init_mpl3115a2.c
@@ -31,7 +31,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define MPL3115A2_NUM     (sizeof(mpl3115a2_params) / sizeof(mpl3115a2_params[0]))
+#define MPL3115A2_NUM     ARRAY_SIZE(mpl3115a2_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -46,7 +46,7 @@ static saul_reg_t saul_entries[MPL3115A2_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define MPL3115A2_INFO_NUM    (sizeof(mpl3115a2_saul_info) / sizeof(mpl3115a2_saul_info[0]))
+#define MPL3115A2_INFO_NUM    ARRAY_SIZE(mpl3115a2_saul_info)
 
 /**
  * @name    Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_mpu9150.c b/sys/auto_init/saul/auto_init_mpu9150.c
index 9e6a38530f..fa0ca82ce9 100644
--- a/sys/auto_init/saul/auto_init_mpu9150.c
+++ b/sys/auto_init/saul/auto_init_mpu9150.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define MPU9150_NUM         (sizeof(mpu9150_params) / sizeof(mpu9150_params[0]))
+#define MPU9150_NUM         ARRAY_SIZE(mpu9150_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[MPU9150_NUM * 3];
 /**
  * @brief   Define the number of saul info
  */
-#define MPU9150_INFO_NUM    (sizeof(mpu9150_saul_info) / sizeof(mpu9150_saul_info[0]))
+#define MPU9150_INFO_NUM    ARRAY_SIZE(mpu9150_saul_info)
 
 /**
  * @name    Reference the driver structs
diff --git a/sys/auto_init/saul/auto_init_pir.c b/sys/auto_init/saul/auto_init_pir.c
index d01b1217c6..357132b0f3 100644
--- a/sys/auto_init/saul/auto_init_pir.c
+++ b/sys/auto_init/saul/auto_init_pir.c
@@ -28,7 +28,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define PIR_NUM    (sizeof(pir_params)/sizeof(pir_params[0]))
+#define PIR_NUM    ARRAY_SIZE(pir_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
diff --git a/sys/auto_init/saul/auto_init_pulse_counter.c b/sys/auto_init/saul/auto_init_pulse_counter.c
index b0ca423648..61f1843ad0 100644
--- a/sys/auto_init/saul/auto_init_pulse_counter.c
+++ b/sys/auto_init/saul/auto_init_pulse_counter.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define PULSE_COUNTER_NUM    (sizeof(pulse_counter_params) / sizeof(pulse_counter_params[0]))
+#define PULSE_COUNTER_NUM    ARRAY_SIZE(pulse_counter_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -44,7 +44,7 @@ static saul_reg_t saul_entries[PULSE_COUNTER_NUM];
 /**
  * @brief   Define the number of configured sensors
  */
-#define PULSE_COUNTER_INFO_NUM    (sizeof(pulse_counter_saul_info) / sizeof(pulse_counter_saul_info[0]))
+#define PULSE_COUNTER_INFO_NUM    ARRAY_SIZE(pulse_counter_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_sds011.c b/sys/auto_init/saul/auto_init_sds011.c
index f5874b6f49..a807d77c55 100644
--- a/sys/auto_init/saul/auto_init_sds011.c
+++ b/sys/auto_init/saul/auto_init_sds011.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define SDS011_NUM     (sizeof(sds011_params) / sizeof(sds011_params[0]))
+#define SDS011_NUM     ARRAY_SIZE(sds011_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[SDS011_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define SDS011_INFO_NUM (sizeof(sds011_saul_info) / sizeof(sds011_saul_info[0]))
+#define SDS011_INFO_NUM ARRAY_SIZE(sds011_saul_info)
 
 /**
  * @name    Import SAUL endpoint
diff --git a/sys/auto_init/saul/auto_init_sht1x.c b/sys/auto_init/saul/auto_init_sht1x.c
index 4f49db3275..c4ba6261fe 100644
--- a/sys/auto_init/saul/auto_init_sht1x.c
+++ b/sys/auto_init/saul/auto_init_sht1x.c
@@ -36,7 +36,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define SHT1X_NUM     (sizeof(sht1x_params) / sizeof(sht1x_params[0]))
+#define SHT1X_NUM     ARRAY_SIZE(sht1x_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
diff --git a/sys/auto_init/saul/auto_init_sht3x.c b/sys/auto_init/saul/auto_init_sht3x.c
index 8093166eca..5e9a90be58 100644
--- a/sys/auto_init/saul/auto_init_sht3x.c
+++ b/sys/auto_init/saul/auto_init_sht3x.c
@@ -24,7 +24,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define SHT3X_NUM      (sizeof(sht3x_params) / sizeof(sht3x_params[0]))
+#define SHT3X_NUM      ARRAY_SIZE(sht3x_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -39,7 +39,7 @@ static saul_reg_t saul_entries[SHT3X_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define SHT3X_INFO_NUM (sizeof(sht3x_saul_info) / sizeof(sht3x_saul_info[0]))
+#define SHT3X_INFO_NUM ARRAY_SIZE(sht3x_saul_info)
 
 /**
  * @name    Reference the driver structs.
diff --git a/sys/auto_init/saul/auto_init_si114x.c b/sys/auto_init/saul/auto_init_si114x.c
index 21fe84bc56..76cc41eb6c 100644
--- a/sys/auto_init/saul/auto_init_si114x.c
+++ b/sys/auto_init/saul/auto_init_si114x.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define SI114X_NUMOF    (sizeof(si114x_params) / sizeof(si114x_params[0]))
+#define SI114X_NUMOF    ARRAY_SIZE(si114x_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[SI114X_NUMOF * 4];
 /**
  * @brief   Define the number of saul info
  */
-#define SI114X_INFO_NUMOF    (sizeof(si114x_saul_reg_info) / sizeof(si114x_saul_reg_info[0]))
+#define SI114X_INFO_NUMOF    ARRAY_SIZE(si114x_saul_reg_info)
 
 /**
  * @name    Reference the driver structs
diff --git a/sys/auto_init/saul/auto_init_si70xx.c b/sys/auto_init/saul/auto_init_si70xx.c
index 609326e13d..e0b57f3d5f 100644
--- a/sys/auto_init/saul/auto_init_si70xx.c
+++ b/sys/auto_init/saul/auto_init_si70xx.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define SI70XX_NUM    (sizeof(si70xx_params) / sizeof(si70xx_params[0]))
+#define SI70XX_NUM    ARRAY_SIZE(si70xx_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -44,7 +44,7 @@ static saul_reg_t saul_entries[SI70XX_NUM * 2];
 /**
  * @brief   Define the number of saul info
  */
-#define SI70XX_INFO_NUM    (sizeof(si70xx_saul_info) / sizeof(si70xx_saul_info[0]))
+#define SI70XX_INFO_NUM    ARRAY_SIZE(si70xx_saul_info)
 
 /**
  * @name    Reference the driver structs.
diff --git a/sys/auto_init/saul/auto_init_tcs37727.c b/sys/auto_init/saul/auto_init_tcs37727.c
index 1f3ea8018a..eab392a99a 100644
--- a/sys/auto_init/saul/auto_init_tcs37727.c
+++ b/sys/auto_init/saul/auto_init_tcs37727.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define TCS37727_NUM    (sizeof(tcs37727_params) / sizeof(tcs37727_params[0]))
+#define TCS37727_NUM    ARRAY_SIZE(tcs37727_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -45,7 +45,7 @@ static saul_reg_t saul_entries[TCS37727_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define TCS37727_INFO_NUM    (sizeof(tcs37727_saul_info) / sizeof(tcs37727_saul_info[0]))
+#define TCS37727_INFO_NUM    ARRAY_SIZE(tcs37727_saul_info)
 
 /**
  * @brief   Export the sensor's SAUL interface
diff --git a/sys/auto_init/saul/auto_init_tmp006.c b/sys/auto_init/saul/auto_init_tmp006.c
index 77fbdd5e6b..61261e8252 100644
--- a/sys/auto_init/saul/auto_init_tmp006.c
+++ b/sys/auto_init/saul/auto_init_tmp006.c
@@ -31,7 +31,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define TMP006_NUM     (sizeof(tmp006_params) / sizeof(tmp006_params[0]))
+#define TMP006_NUM     ARRAY_SIZE(tmp006_params)
 
 /**
  * @brief   Allocate memory for the device descriptors
@@ -46,7 +46,7 @@ static saul_reg_t saul_entries[TMP006_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define TMP006_INFO_NUM    (sizeof(tmp006_saul_info) / sizeof(tmp006_saul_info[0]))
+#define TMP006_INFO_NUM    ARRAY_SIZE(tmp006_saul_info)
 
 /**
  * @brief   Reference the driver struct
diff --git a/sys/auto_init/saul/auto_init_tsl2561.c b/sys/auto_init/saul/auto_init_tsl2561.c
index ee15bf9c8d..311d2a0670 100644
--- a/sys/auto_init/saul/auto_init_tsl2561.c
+++ b/sys/auto_init/saul/auto_init_tsl2561.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define TSL2561_NUMOF    (sizeof(tsl2561_params) / sizeof(tsl2561_params[0]))
+#define TSL2561_NUMOF    ARRAY_SIZE(tsl2561_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -44,7 +44,7 @@ static saul_reg_t saul_entries[TSL2561_NUMOF];
 /**
  * @brief   Define the number of saul info
  */
-#define TSL2561_INFO_NUMOF    (sizeof(tsl2561_saul_info) / sizeof(tsl2561_saul_info[0]))
+#define TSL2561_INFO_NUMOF    ARRAY_SIZE(tsl2561_saul_info)
 
 /**
  * @brief   Reference the driver structs.
diff --git a/sys/auto_init/saul/auto_init_tsl4531x.c b/sys/auto_init/saul/auto_init_tsl4531x.c
index 0496666df1..0646d99752 100644
--- a/sys/auto_init/saul/auto_init_tsl4531x.c
+++ b/sys/auto_init/saul/auto_init_tsl4531x.c
@@ -32,7 +32,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define TSL4531X_NUMOF    (sizeof(tsl4531x_params) / sizeof(tsl4531x_params[0]))
+#define TSL4531X_NUMOF    ARRAY_SIZE(tsl4531x_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -48,7 +48,7 @@ static saul_reg_t saul_entries[TSL4531X_NUMOF];
 /**
  * @brief   Define the number of saul info
  */
-#define TSL4531X_INFO_NUMOF    (sizeof(tsl4531x_saul_info) / sizeof(tsl4531x_saul_info[0]))
+#define TSL4531X_INFO_NUMOF    ARRAY_SIZE(tsl4531x_saul_info)
 
 /**
  * @brief   Reference the driver structs.
diff --git a/sys/auto_init/saul/auto_init_vcnl40x0.c b/sys/auto_init/saul/auto_init_vcnl40x0.c
index b8d1e3feda..c0a1254620 100644
--- a/sys/auto_init/saul/auto_init_vcnl40x0.c
+++ b/sys/auto_init/saul/auto_init_vcnl40x0.c
@@ -30,7 +30,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define VCNL40X0_NUMOF    (sizeof(vcnl40x0_params) / sizeof(vcnl40x0_params[0]))
+#define VCNL40X0_NUMOF    ARRAY_SIZE(vcnl40x0_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
diff --git a/sys/auto_init/saul/auto_init_veml6070.c b/sys/auto_init/saul/auto_init_veml6070.c
index 72559e94f2..6e8fc38962 100644
--- a/sys/auto_init/saul/auto_init_veml6070.c
+++ b/sys/auto_init/saul/auto_init_veml6070.c
@@ -29,7 +29,7 @@
 /**
  * @brief   Define the number of configured sensors
  */
-#define VEML6070_NUM    (sizeof(veml6070_params) / sizeof(veml6070_params[0]))
+#define VEML6070_NUM    ARRAY_SIZE(veml6070_params)
 
 /**
  * @brief   Allocation of memory for device descriptors
@@ -44,7 +44,7 @@ static saul_reg_t saul_entries[VEML6070_NUM];
 /**
  * @brief   Define the number of saul info
  */
-#define VEML6070_INFO_NUM    (sizeof(veml6070_saul_info) / sizeof(veml6070_saul_info[0]))
+#define VEML6070_INFO_NUM    ARRAY_SIZE(veml6070_saul_info)
 
 /**
  * @brief   Reference the driver structs.
diff --git a/sys/auto_init/storage/auto_init_sdcard_spi.c b/sys/auto_init/storage/auto_init_sdcard_spi.c
index 1e57be14e7..d18e3b3240 100644
--- a/sys/auto_init/storage/auto_init_sdcard_spi.c
+++ b/sys/auto_init/storage/auto_init_sdcard_spi.c
@@ -29,7 +29,7 @@
  * @brief   number of used sd cards
  * @{
  */
-#define SDCARD_SPI_NUM (sizeof(sdcard_spi_params) / sizeof(sdcard_spi_params[0]))
+#define SDCARD_SPI_NUM ARRAY_SIZE(sdcard_spi_params)
 /** @} */
 
 /**
diff --git a/sys/fmt/fmt.c b/sys/fmt/fmt.c
index 1e70126931..d0d96b354f 100644
--- a/sys/fmt/fmt.c
+++ b/sys/fmt/fmt.c
@@ -46,7 +46,7 @@ static const uint32_t _tenmap[] = {
     10000000LU,
 };
 
-#define TENMAP_SIZE  (sizeof(_tenmap) / sizeof(_tenmap[0]))
+#define TENMAP_SIZE  ARRAY_SIZE(_tenmap)
 
 static inline int _is_digit(char c)
 {
diff --git a/sys/include/embUnit.h b/sys/include/embUnit.h
index f8d4045d26..32ec3331ad 100644
--- a/sys/include/embUnit.h
+++ b/sys/include/embUnit.h
@@ -22,6 +22,7 @@
 #define EMBUNIT_H
 
 #include "embUnit/embUnit.h"
+#include "kernel_defines.h"
 
 #ifdef OUTPUT
 #   define OUTPUT_XML       (1)
diff --git a/sys/include/phydat.h b/sys/include/phydat.h
index d56f968ed1..ff5569af58 100644
--- a/sys/include/phydat.h
+++ b/sys/include/phydat.h
@@ -36,6 +36,7 @@
 #define PHYDAT_H
 
 #include <stdint.h>
+#include "kernel_defines.h"
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/sys/net/application_layer/gcoap/gcoap.c b/sys/net/application_layer/gcoap/gcoap.c
index 04d4bae326..bce460ea7c 100644
--- a/sys/net/application_layer/gcoap/gcoap.c
+++ b/sys/net/application_layer/gcoap/gcoap.c
@@ -62,7 +62,7 @@ const coap_resource_t _default_resources[] = {
 
 static gcoap_listener_t _default_listener = {
     &_default_resources[0],
-    sizeof(_default_resources) / sizeof(_default_resources[0]),
+    ARRAY_SIZE(_default_resources),
     NULL,
     NULL
 };
diff --git a/sys/net/gnrc/application_layer/tftp/gnrc_tftp.c b/sys/net/gnrc/application_layer/tftp/gnrc_tftp.c
index 474cdff710..e787ba84e3 100644
--- a/sys/net/gnrc/application_layer/tftp/gnrc_tftp.c
+++ b/sys/net/gnrc/application_layer/tftp/gnrc_tftp.c
@@ -53,7 +53,6 @@ static kernel_pid_t _tftp_kernel_pid;
 #endif
 
 #define MIN(a, b)                   ((a) > (b) ? (b) : (a))
-#define ARRAY_LEN(x)                (sizeof(x) / sizeof(x[0]))
 
 #define TFTP_TIMEOUT_MSG            0x4000
 #define TFTP_STOP_SERVER_MSG        0x4001
@@ -1079,7 +1078,7 @@ int _tftp_decode_start(tftp_context_t *ctxt, gnrc_pktsnip_t *inpkt, gnrc_pktsnip
     DEBUG("tftp: incoming request '%s', mode: %s\n", ctxt->file_name, str_mode);
 
     /* decode the TFTP transfer mode */
-    for (uint32_t idx = 0; idx < ARRAY_LEN(_tftp_modes); ++idx) {
+    for (uint32_t idx = 0; idx < ARRAY_SIZE(_tftp_modes); ++idx) {
         if (_tftp_modes[idx].len > (inpkt->size - sizeof(*hdr) - fnlen)) {
             continue;
         }
@@ -1110,7 +1109,7 @@ int _tftp_decode_options(tftp_context_t *ctxt, gnrc_pktsnip_t *buf, uint32_t sta
         offset += strlen(value) + 1;
 
         /* check what option we are parsing */
-        for (uint32_t idx = 0; idx < ARRAY_LEN(_tftp_options); ++idx) {
+        for (uint32_t idx = 0; idx < ARRAY_SIZE(_tftp_options); ++idx) {
             if (memcmp(name, _tftp_options[idx].name, _tftp_options[idx].len) == 0) {
                 /* set the option value of the known options */
                 switch (idx) {
diff --git a/sys/net/gnrc/application_layer/uhcpc/gnrc_uhcpc.c b/sys/net/gnrc/application_layer/uhcpc/gnrc_uhcpc.c
index 5b9a085cf6..7299bf22cf 100644
--- a/sys/net/gnrc/application_layer/uhcpc/gnrc_uhcpc.c
+++ b/sys/net/gnrc/application_layer/uhcpc/gnrc_uhcpc.c
@@ -129,7 +129,7 @@ static void* uhcp_client_thread(void *arg)
 {
     (void)arg;
 
-    msg_init_queue(_uhcp_msg_queue, sizeof(_uhcp_msg_queue)/sizeof(msg_t));
+    msg_init_queue(_uhcp_msg_queue, ARRAY_SIZE(_uhcp_msg_queue));
     uhcp_client(gnrc_border_interface);
     return NULL;
 }
diff --git a/sys/net/routing/nhdp/nhdp_reader.c b/sys/net/routing/nhdp/nhdp_reader.c
index f29d6e2f32..f74bf3e43d 100644
--- a/sys/net/routing/nhdp/nhdp_reader.c
+++ b/sys/net/routing/nhdp/nhdp_reader.c
@@ -108,9 +108,9 @@ void nhdp_reader_init(void)
 
     /* Register HELLO message consumer */
     rfc5444_reader_add_message_consumer(&reader, &_nhdp_msg_consumer,
-                                        _nhdp_msg_tlvs, ARRAYSIZE(_nhdp_msg_tlvs));
+                                        _nhdp_msg_tlvs, ARRAY_SIZE(_nhdp_msg_tlvs));
     rfc5444_reader_add_message_consumer(&reader, &_nhdp_address_consumer,
-                                        _nhdp_addr_tlvs, ARRAYSIZE(_nhdp_addr_tlvs));
+                                        _nhdp_addr_tlvs, ARRAY_SIZE(_nhdp_addr_tlvs));
 }
 
 int nhdp_reader_handle_packet(kernel_pid_t rcvg_if_pid, void *buffer, size_t length)
diff --git a/sys/net/routing/nhdp/nhdp_writer.c b/sys/net/routing/nhdp/nhdp_writer.c
index 8caa80dddf..22be9d1497 100644
--- a/sys/net/routing/nhdp/nhdp_writer.c
+++ b/sys/net/routing/nhdp/nhdp_writer.c
@@ -90,7 +90,7 @@ void nhdp_writer_init(void)
 
     /* Register HELLO msg with 16 byte addresses and content provider */
     rfc5444_writer_register_msgcontentprovider(&nhdp_writer,
-            &_nhdp_message_content_provider, _nhdp_addrtlvs, ARRAYSIZE(_nhdp_addrtlvs));
+            &_nhdp_message_content_provider, _nhdp_addrtlvs, ARRAY_SIZE(_nhdp_addrtlvs));
     _hello_msg = rfc5444_writer_register_message(&nhdp_writer, RFC5444_MSGTYPE_HELLO, false, 16);
     _hello_msg->addMessageHeader = _nhdp_add_hello_msg_header_cb;
 
diff --git a/sys/phydat/phydat.c b/sys/phydat/phydat.c
index 7c8dd82df0..8fb96974c3 100644
--- a/sys/phydat/phydat.c
+++ b/sys/phydat/phydat.c
@@ -56,11 +56,11 @@ static const uint32_t divisors[] = {
     10,
 };
 
-#define LOOKUP_LEN (sizeof(lookup_table_positive) / sizeof(int32_t))
+#define LOOKUP_LEN ARRAY_SIZE(lookup_table_positive)
 
 void phydat_fit(phydat_t *dat, const int32_t *values, unsigned int dim)
 {
-    assert(dim <= (sizeof(dat->val) / sizeof(dat->val[0])));
+    assert(dim <= ARRAY_SIZE(dat->val));
     uint32_t divisor = 0;
     uint32_t max = 0;
     const uint32_t *lookup = lookup_table_positive;
diff --git a/sys/riotboot/slot.c b/sys/riotboot/slot.c
index 0a0df2c78d..fa4b79738c 100644
--- a/sys/riotboot/slot.c
+++ b/sys/riotboot/slot.c
@@ -40,7 +40,7 @@ const riotboot_hdr_t * const riotboot_slots[] = {
 };
 
 /* Calculate the number of slots */
-const unsigned riotboot_slot_numof = sizeof(riotboot_slots) / sizeof(riotboot_hdr_t*);
+const unsigned riotboot_slot_numof = ARRAY_SIZE(riotboot_slots);
 
 static void _riotboot_slot_jump_to_image(const riotboot_hdr_t *hdr)
 {
diff --git a/sys/shell/commands/sc_gnrc_netif.c b/sys/shell/commands/sc_gnrc_netif.c
index b6404c656a..dda9df911d 100644
--- a/sys/shell/commands/sc_gnrc_netif.c
+++ b/sys/shell/commands/sc_gnrc_netif.c
@@ -44,11 +44,6 @@
  */
 #define _LINE_THRESHOLD                 (8U)
 
-/**
- * @brief   Determine length of array in elements
- */
-#define _ARRAY_LEN(x)                   (sizeof(x) / sizeof(x[0]))
-
 /**
  * @brief   Flag command mapping
  *
@@ -177,9 +172,9 @@ static void _set_usage(char *cmd_name)
 static void _flag_usage(char *cmd_name)
 {
     printf("usage: %s <if_id> [-]{", cmd_name);
-    for (unsigned i = 0; i < _ARRAY_LEN(flag_cmds); i++) {
+    for (unsigned i = 0; i < ARRAY_SIZE(flag_cmds); i++) {
         printf("%s", flag_cmds[i].name);
-        if (i < (_ARRAY_LEN(flag_cmds) - 1)) {
+        if (i < (ARRAY_SIZE(flag_cmds) - 1)) {
             printf("|");
         }
     }
@@ -1073,7 +1068,7 @@ static int _netif_flag(char *cmd, kernel_pid_t iface, char *flag)
         set = NETOPT_DISABLE;
         flag++;
     }
-    for (unsigned i = 0; i < _ARRAY_LEN(flag_cmds); i++) {
+    for (unsigned i = 0; i < ARRAY_SIZE(flag_cmds); i++) {
         if (strcmp(flag_cmds[i].name, flag) == 0) {
             return _netif_set_flag(iface, flag_cmds[i].opt, set);
         }
diff --git a/sys/shell/commands/sc_sht1x.c b/sys/shell/commands/sc_sht1x.c
index a0aa8e816f..1cd1627c97 100644
--- a/sys/shell/commands/sc_sht1x.c
+++ b/sys/shell/commands/sc_sht1x.c
@@ -27,7 +27,7 @@
 #include "sht1x.h"
 #include "sht1x_params.h"
 
-#define SHT1X_NUM     (sizeof(sht1x_params) / sizeof(sht1x_params[0]))
+#define SHT1X_NUM     ARRAY_SIZE(sht1x_params)
 
 extern sht1x_dev_t sht1x_devs[SHT1X_NUM];
 
diff --git a/sys/shell/shell.c b/sys/shell/shell.c
index 880d320b0f..5f723c22aa 100644
--- a/sys/shell/shell.c
+++ b/sys/shell/shell.c
@@ -63,7 +63,7 @@ static shell_command_handler_t find_handler(const shell_command_t *command_list,
     const shell_command_t *entry;
 
     /* iterating over command_lists */
-    for (unsigned int i = 0; i < sizeof(command_lists) / sizeof(entry); i++) {
+    for (unsigned int i = 0; i < ARRAY_SIZE(command_lists); i++) {
         if ((entry = command_lists[i])) {
             /* iterating over commands in command_lists entry */
             while (entry->name != NULL) {
@@ -95,7 +95,7 @@ static void print_help(const shell_command_t *command_list)
     const shell_command_t *entry;
 
     /* iterating over command_lists */
-    for (unsigned int i = 0; i < sizeof(command_lists) / sizeof(entry); i++) {
+    for (unsigned int i = 0; i < ARRAY_SIZE(command_lists); i++) {
         if ((entry = command_lists[i])) {
             /* iterating over commands in command_lists entry */
             while (entry->name != NULL) {