diff --git a/constants.py b/constants.py
index b0ddc14..c7c46e5 100644
--- a/constants.py
+++ b/constants.py
@@ -21,9 +21,10 @@ LOGCONF = {
 }
 
 EMAIL = "email address"
-URL = "URL"
+URL = "url"
 DOMAIN = "domain"
-IPV4 = "IPv4"
-IPV6 = "IPv6"
+IPV4 = "ipv4"
+IPV6 = "ipv6"
+NO_HOST = "no host"
 
 domain_lookup = {}