diff --git a/GoogleDorker.py b/GoogleDorker.py
index d6cdc47..c7da630 100644
--- a/GoogleDorker.py
+++ b/GoogleDorker.py
@@ -99,7 +99,7 @@ def vendork(domain):
     f.close()
 
 options = get_arguments()
-if options.domain:
+if options.domain and re.match("^((?!-))(xn--)?[a-z0-9][a-z0-9-_]{0,61}[a-z0-9]{0,1}\.(xn--)?([a-z0-9\-]{1,61}|[a-z0-9-]{1,30}\.[a-z]{2,})$", options.domain):
     google_dork(options.domain)
     vendork(options.domain)
     print("\n[+] Success. Please check the newly created files.")