diff --git a/libs/string.h b/libs/string.h
index 343c951..b031ba7 100644
--- a/libs/string.h
+++ b/libs/string.h
@@ -36,18 +36,22 @@ void strCopy(string* s1, string* s2) {
 // -------------------------------------
 // CONVERT - different convert to str
 // -------------------------------------
+int numLen(double num) {
+    return snprintf(NULL, 0, "%lf", num);
+}
+
 char* int2Str(int* num) {
-    char* buffer = malloc(12);
+    char* buffer = malloc(numLen(*num) + 2);
     sprintf(buffer, "%d", *num);
     return buffer;
 }
 char* float2Str(float* num) {
-    char* buffer = malloc(41);
+    char* buffer = malloc(numLen(*num) + 2);
     sprintf(buffer, "%f", *num);
     return buffer;
 }
 char* double2Str(double* num) {
-    char* buffer = malloc(311);
+    char* buffer = malloc(numLen(*num) + 2);
     sprintf(buffer, "%lf", *num);
     return buffer;
 }