How to remove your Duolingo account
Be logged in; use the removal link.
Direct removal link: http://www.duolingo.com/settings/deactivate
Helpful Trick: Removing online data
Helpful Trick: Remove third-party logins
If you signed up for Duolingo using a third-party login such as Facebook or Twitter, you probably want to revoke all access from Duolingo. Click here to find out how.