diff --git a/src/numex.c b/src/numex.c
index 1004794e..354f79d7 100644
--- a/src/numex.c
+++ b/src/numex.c
@@ -8,8 +8,6 @@
 
 #define SEPARATOR_TOKENS "-"
 
-#define INT64_MAX_STRING_SIZE 21
-
 #define FLOOR_LOG_BASE(num, base) floor((log((float)num) / log((float)base)) + 0.00001)
 
 numex_table_t *numex_table = NULL;
diff --git a/src/string_utils.h b/src/string_utils.h
index bcf1ccec..1e38bc1d 100644
--- a/src/string_utils.h
+++ b/src/string_utils.h
@@ -15,6 +15,8 @@ extern "C" {
 
 #define MAX_UTF8_CHAR_SIZE 4
 
+#define INT32_MAX_STRING_SIZE 11
+#define INT64_MAX_STRING_SIZE 21
 
 #define UTF8PROC_OPTIONS_BASE UTF8PROC_NULLTERM | UTF8PROC_STABLE