Public API endpoint to check for 6.5B known passwords

In plain words

This developer tool provides an API endpoint that checks passwords against a database of 6.5 billion known compromised passwords. It helps developers verify whether user passwords have appeared in previous data breaches. The service is designed for teams building authentication systems who want to prevent users from choosing passwords that are already publicly exposed and potentially vulnerable to account takeover attacks.

written from the facts on this page · September 2026

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