Password & Data Breach Checker

Discover whether your password has been exposed in major global security breaches. 100% processed client-side in your browser; passwords never leave your device.

k-Anonymity Zero-Knowledge Privacy Multi-Source Fallback Engine
Privacy Guarantee: Your password is hashed locally (client-side) using k-Anonymity. Nobody can view your password.

Checking...

Enter password to test

Enter or paste a password to check for breaches...

WARNING: PASSWORD EXPOSED IN DATA BREACH!

This password has been identified in publicly available breach datasets. Attackers routinely employ credential stuffing with these compromised lists. CHANGE THIS PASSWORD IMMEDIATELY!

HIBP 120ms
Times seen in data breaches
0

SAFE: NO KNOWN BREACH DETECTED

This password was not found in our database of over 10 billion compromised credentials. Review the strength criteria below to ensure it is resilient against brute-force attacks.

HIBP 110ms
Times seen in data breaches
0
CHECK FAILED / NETWORK ERROR

Unable to connect to breach data sources. Please select a different source from the dropdown or verify your internet connection.

Password Strength & Complexity Analysis
0 / 100 Very Weak
Shannon Entropy
0 bits
Độ dài ký tự
0
Online Attack (Rate-Limited): Ngay lập tức
Offline Attack (High-End GPU Rig): Ngay lập tức
Security Standards (NIST & OWASP)
Minimum length of 12 characters
Contains uppercase letters (A-Z)
Contains lowercase letters (a-z)
Contains numbers (0-9)
Contains special characters (!@#$%...)
Avoids keyboard walks & sequences (123, abc, qwerty)
Avoids repeated characters (aaa, 111)
Suggested Secure Alternatives

If your password has leaked or shows low complexity, generate and copy a resilient replacement below:

High-Entropy Random Password
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Memorable 4-Word Passphrase
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How k-Anonymity Works
1. Your browser calculates the SHA-1 hash of the password (40 characters)
2. The first 5 characters are separated as the query prefix
3. The 5-character prefix is sent to the server to fetch ~500 candidate hashes
4. Your browser matches the remaining 35 characters locally in memory

About the Password & Data Breach Checker

The Password & Data Breach Checker empowers you to find out whether your password has surfaced in leaked credential databases compiled from thousands of security incidents worldwide.

By utilizing the k-Anonymity mathematical privacy model and standard cryptographic hashing (SHA-1 / Keccak-512), your password is evaluated entirely inside your browser. No plaintext password or full hash is ever sent across the wire.

Our system features a resilient multi-source architecture with automatic failover (Have I Been Pwned API, Vuiz Cloud Gateway Cache, and XposedOrNot API) to ensure uninterrupted, high-speed checks even during network interruptions.

Key features

  • k-Anonymity Zero-Knowledge Privacy Only the first 5 characters of your SHA-1 hash are queried. The remaining 35 characters are compared locally in your browser memory, eliminating any eavesdropping risk.
  • Multi-Source Fallback System Directly queries Have I Been Pwned database of 10+ billion leaked credentials, gracefully falling back to Vuiz Gateway Cache and XposedOrNot if ad-blockers or network timeouts occur.
  • Strength Scoring & Crack Time Estimation Calculates Shannon entropy, verifies NIST SP 800-63B guidelines, and estimates brute-force crack time against modern high-performance GPU clusters.
  • Instant Secure Password Generator Automatically generates cryptographically secure alternatives or memorable 4-word passphrases with 1-click clipboard copy.

How to check if your password has been breached

Follow these 4 simple steps to safely inspect breach exposure and upgrade your credential security.

  1. Enter the password to test Type or paste the password into the input field. You can click the eye icon to toggle masking, or click "Sample" to try a demo password.
  2. Select verification source mode Keep the default "Automatic" mode for smart multi-source fallback, or specifically pick Have I Been Pwned or XposedOrNot.
  3. Review breach verdict and count Inspect the verdict card to see the exact number of times this password appeared in known public credential breaches.
  4. Inspect strength metrics and generate alternatives If the password is breached or weak, review criteria checklist and copy one of the suggested high-entropy passwords or passphrases.

Usage tips

  • Never reuse the same password across critical accounts like Primary Email, Online Banking, and Social Networks.
  • Even long and complex passwords become unsafe once published in breach dumps, as attackers use automated credential-stuffing tools.
  • Enable multi-factor authentication (2FA) with an authenticator app (such as Google Authenticator) or hardware security key wherever available.
  • Rely on a reputable password manager to generate and store unique, 16+ character passwords for every service you use.

Frequently asked questions

Yes, 100% safe. This tool employs the Have I Been Pwned k-Anonymity model: your password is encrypted into a SHA-1 hash locally in your web browser. Only the first 5 hexadecimal characters of the hash are transmitted. The server returns hundreds of matching candidate hashes, and your browser completes the suffix match locally. Neither Vuiz nor any third party ever receives your password or your complete hash.
By default, the tool performs a direct client-side query to Have I Been Pwned. If client-side extensions (such as privacy shields or ad-blockers) block third-party API calls, the tool automatically routes through our Vuiz Gateway Proxy or queries XposedOrNot, ensuring reliable verification under all network conditions.
It means the password has not surfaced in tracked global data breaches. However, if the password is too short or predictable (such as names or birthdates), it could still be cracked via dictionary or brute-force attacks. Ensure your password also passes the strength and entropy checklist.
Immediately change this password on every platform where you have used it. Ensure 2FA is activated and terminate any unrecognized active sessions.
k-Anonymity is a mathematical security property ensuring that an entity cannot be distinguished from at least k-1 other entities. Sending only a 5-character hash prefix returns ~500 to 1,000 distinct hash suffixes, leaving external servers with zero knowledge of which specific hash belongs to your password.