diff --git a/src/input.c b/src/input.c
index 32e9d761..b0bb3de4 100644
--- a/src/input.c
+++ b/src/input.c
@@ -1086,8 +1086,8 @@ GLFWAPI int glfwUpdateGamepadMappings(const char* string)
     while (*c)
     {
         if ((*c >= '0' && *c <= '9') ||
-            (*c >= 'a' && *c <= 'z') ||
-            (*c >= 'A' && *c <= 'Z'))
+            (*c >= 'a' && *c <= 'f') ||
+            (*c >= 'A' && *c <= 'F'))
         {
             char line[1024];