diff --git a/valid/valid.go b/valid/valid.go
index e01ac07b393fa0b38a68d7cec590f46451be4eda..2337a374c7e0ac8090f45f6344ab7e6bcf0fbbad 100644
--- a/valid/valid.go
+++ b/valid/valid.go
@@ -47,7 +47,7 @@ 	}
 	if o, ok := valid.input[name]; ok {
 		s, ok := o.(string)
 		valid.
-			Expect(ok, fmt.Sprintf("Expected {} to be a string", name)).
+			Expect(ok, fmt.Sprintf("Expected %s to be a string", name)).
 			WithField(name)
 		if ok {
 			fn(s)