diff --git a/lib/urlapi.c b/lib/urlapi.c
index 03efccd7b4..a0ee331dab 100644
--- a/lib/urlapi.c
+++ b/lib/urlapi.c
@@ -597,7 +597,7 @@ static CURLUcode hostname_check(struct Curl_URL *u, char *hostname)
 
   if(hostname[0] == '[') {
     char dest[16]; /* fits a binary IPv6 address */
-    const char *l = "0123456789abcdefABCDEF::.";
+    const char *l = "0123456789abcdefABCDEF:.";
     hostname++;
     hlen -= 2;