diff --git a/binding/form_mapping.go b/binding/form_mapping.go
index 77a1bde6..f928c4ce 100644
--- a/binding/form_mapping.go
+++ b/binding/form_mapping.go
@@ -377,11 +377,8 @@ func setTimeDuration(val string, value reflect.Value) error {
 }
 
 func head(str, sep string) (head string, tail string) {
-	idx := strings.Index(str, sep)
-	if idx < 0 {
-		return str, ""
-	}
-	return str[:idx], str[idx+len(sep):]
+	head, tail, _ = strings.Cut(str, sep)
+	return head, tail
 }
 
 func setFormMap(ptr any, form map[string][]string) error {