diff --git a/d1/dynu_update.py b/d1/dynu_update.py
index 052b7c7..609f012 100644
--- a/d1/dynu_update.py
+++ b/d1/dynu_update.py
@@ -43,7 +43,7 @@ logging.warning('got dynu_redirect')
 
 NGROK_DOMAIN = sys.argv[2]
 t6 = requests.get('http://%s:4040/api/tunnels' % NGROK_DOMAIN).json()
-TUNNEL_URL = t6['tunnels'][0]['public_url']
+TUNNEL_URL = t6['tunnels'][0]['public_url'].replace('http://', 'https://')
 logging.warning('got tunnel_url')