Password Breach Checker
Check if your password has been exposed in data breaches. Search billions of leaked passwords to verify if your credentials are compromised and at risk.
Your password is hashed locally. Only the first 5 characters of the hash are sent to the API.
Check If Your Password Was Breached
Enter any password above to check if it has been exposed in known data breaches. Your password is hashed locally and never leaves your browser.
How Our Password Breach Checker Works
Secure K-Anonymity
Your password is hashed using SHA-1, and only the first 5 characters of the hash are sent to check against the database. The full comparison happens in your browser, ensuring your actual password never leaves your device.
Pwned Passwords Database
We check against the Have I Been Pwned Passwords database containing over 10 billion compromised passwords from major data breaches worldwide, continuously updated with new breaches.
Instant Results
Get immediate results showing if your password was found in breaches, how many times it appears, and actionable steps to secure your accounts immediately.
Our breach checker uses k-anonymity to protect your privacy. This technique, developed by security researchers, allows us to check if your password is compromised without ever knowing what your password is. Your password is hashed locally, only a small prefix is sent for lookup, and the final comparison happens in your browser.
Why You Should Check Your Passwords for Breaches
Prevent Account Takeovers
If your password appears in breach databases, hackers already have it and can use it to access your accounts. Credential stuffing attacks use leaked passwords to try logging into thousands of websites. By checking and changing compromised passwords, you stay ahead of attackers.
Stop Password Reuse Risks
Many people reuse passwords across multiple sites. If one site is breached and you reuse that password elsewhere, all accounts with that password are at risk. Regular breach checking helps you identify which passwords need immediate replacement.
Proactive Security
Data breaches happen constantly, but companies often delay notifying users. Proactively checking your passwords lets you discover compromises before attackers exploit them, giving you time to change passwords and secure accounts before damage occurs.
Frequently Asked Questions
How does a password breach checker work?
A password breach checker compares your password against databases of known leaked passwords from data breaches. When companies are hacked, stolen passwords are often leaked online. Our tool uses SHA-1 hashing and k-anonymity to check your password securely without exposing it to our servers.
Is it safe to check my password for breaches?
Yes, our breach checker is completely safe. We use SHA-1 hashing with k-anonymity, which means only a partial hash of your password is sent for checking. Your actual password never leaves your browser and is never stored anywhere. The final comparison happens locally in your device.
What should I do if my password was breached?
If your password appears in a breach: 1) Change it immediately on all accounts where you use it, 2) Use our password generator to create a new strong password, 3) Enable two-factor authentication (2FA) everywhere possible, 4) Never reuse the compromised password again, and 5) Consider using a password manager to track unique passwords for each account.
How often should I check my passwords for breaches?
Check your passwords for breaches at least once every 3-6 months, or immediately if you hear about a major data breach. Regular monitoring helps you stay ahead of potential security threats. Also check whenever you create a new password to ensure it hasn't been previously compromised.
What is a password data breach?
A password data breach occurs when unauthorized parties gain access to password databases stored by companies or organizations. These leaked passwords are often sold on the dark web or used for credential stuffing attacks, where hackers try the stolen passwords across multiple websites to gain unauthorized access to accounts.
Can I check multiple passwords at once?
Currently, our tool checks one password at a time to maintain privacy and security. This ensures each check is performed securely with k-anonymity protection. For best practices, check all your important passwords individually, especially those used for email, banking, and social media accounts.
Major Password Breaches in Recent Years
LinkedIn (2021)
700M+ passwords
Email addresses, password hashes, names
Facebook (2019)
540M records
Account IDs, passwords, emails
Yahoo (2013-2014)
3B passwords
Passwords, security questions, email
PlayStation (2011)
77M passwords
Passwords, names, addresses, emails
Adobe (2013)
153M passwords
Encrypted passwords, emails, hints
Collection #1 (2019)
773M credentials
Email/password pairs from multiple breaches
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