Photo by Matthew Henry from Burst

There’s a new free extension for Google’s Chrome that can tell users if their passwords have been compromised. The Password Checkup extension will monitor users’ different website logins, and if someone logs in with a username and password that Google knows has been compromised, the user is alerted and warned to change the password.

Users’ passwords and usernames will be encrypted so Google won’t actually be able to see them. Google cross-checks the login credentials against a regularly updated database of more than four billion username and password entries that it has collected from sources such as large databases of usernames and passwords that hackers post online.