diff --git a/uniuri.go b/uniuri.go
index f4b20eb..d487298 100644
--- a/uniuri.go
+++ b/uniuri.go
@@ -26,7 +26,7 @@ const (
 )
 
 // Standard characters allowed in uniuri string.
-var StdChars = []byte("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890")
+var StdChars = []byte("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789")
 
 // New returns a new random string of the standard length, consisting of
 // standard characters.