diff --git a/tests/unittests/tests-uri_parser/tests-uri_parser.c b/tests/unittests/tests-uri_parser/tests-uri_parser.c
index ecc3525882..2ae1a58c4a 100644
--- a/tests/unittests/tests-uri_parser/tests-uri_parser.c
+++ b/tests/unittests/tests-uri_parser/tests-uri_parser.c
@@ -48,8 +48,7 @@
         }                                                                   \
     } while (0)
 
-#define VEC_MSG_LEN (sizeof("Unexpected userinfo member \"\" for \"\"") + \
-                     64U + 8U)
+#define VEC_MSG_LEN   (256)
 
 typedef struct {
     char uri[64];