diff --git a/cpu/kinetis/dist/calc_spi_scalers/calc_spi_scalers.c b/cpu/kinetis/dist/calc_spi_scalers/calc_spi_scalers.c
index a2f1fdad81..029a5de237 100644
--- a/cpu/kinetis/dist/calc_spi_scalers/calc_spi_scalers.c
+++ b/cpu/kinetis/dist/calc_spi_scalers/calc_spi_scalers.c
@@ -28,6 +28,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#define ARRAY_SIZE(a) (sizeof((a)) / sizeof((a)[0]))
+
 /**
  * @brief Targeted SPI bus speed values (pre-defined by RIOT)
  */