Model Username Password
Nest Wifi / Nest Wifi Pro (app only) (app only) No web admin page; use the Google Home app.
Google Wifi (app only) (app only) No web admin page; use the Google Home app.

Change the default password after logging in

Default credentials for Google Nest routers are publicly documented, so if your router still uses one, change the admin password immediately to a strong, unique password. Leaving the default in place lets anyone on your network reconfigure the router. Many newer Google Nest models instead ship with a unique password printed on the device label - if yours does, use that.

How to log in to your Google Nest router

Open a browser and go to http://192.168.86.1, then sign in with the credentials above. Not sure which address is yours? See router login by IP. If you don't know a changed password, you can reset the router to restore the default.