Leaked Username Checker

Leaked Username Lookup

Check any username to see if it has been leaked online.

Free Leaked Username Checker

IPQS leaked username checker searches are powered by our automated scanners which analyze billions of leaked credentials exposed online from thousands of database breaches. New breaches are automatically discovered.

Real-Time Leaked Username Detection Via API or Bulk Processing

Integrate leaked username checks against database breaches online through a real-time API, or by uploading a bulk list directly through the IPQS user dashboard. Leaked username verification can greatly limit abusive behavior through credential stuffing detection and abuse from account opening fraud using stolen credentials.

Check leaked usernames directly from your website, software, or app with the IPQS leaked username lookup API which includes example code to make integration an easy process. The leaked username checker can be performed live during account registration, user login, and other sensitive actions.

Detect leaked usernames with one simple API lookup. Improve user data and account creation quality with accurate leaked username lookups that check thousands of databases across billions of exposed records online.

How Does Leaked Username Detection Work?

Search any username against our leaked database consisting of over 5 billion leaked usernames from over 3700+ data breaches online. IPQS uses automated scanners that parse leaked data and compromised credentials from private forums, chat groups, dark web, and similar sources.

Our leaked username lookup tool works best with additional verification such as our compromised password checks and leaked email detection, for complete user protection.

What Leaked Username Lookup Data Is Available?

Deploy the leaked username verification API or utilize our bulk list processing tools to detect if the username has been exposed in a public or privately listed data breach online. Our tools will also append the name of the companies or database breaches where the username was leaked online as well as the date of the breach. This makes it easy to identify a leaked username that likely represent a fraudulent user with a compromised username.

API Lookup Access

Easy API Lookups

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