Google has released a new Chrome extension that automatically checks and lets you know if any of your passwords are secure or not.
The extension is called Password Checkup. There are other companies that offer this service, but the one from Google seems to be the easiest to use.
Once the extension is installed in Chrome it will check any of the login details that you use.
If any of your passwords are found to have been breached you will be alerted and told to change it
Note: Remember to make sure that you use a different password for every website that you login to and consider using Two factor Authentication when available.