Password Breach Checker — Free Online Tool
Check if your password has been in a data breach
Check if your password has been leaked in a data breach. Uses HaveIBeenPwned k-anonymity API — your password never leaves your browser.
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Free password breach checker — HaveIBeenPwned integration
Check if your password has been leaked in a data breach. Uses HaveIBeenPwned\'s k-anonymity API — your password never leaves your device. Database contains 850M+ leaked passwords from real breaches.
How to use this tool
- 1
Type your password
Enter the password you want to check. We hash it locally — only the first 5 characters of the hash ever leave your browser.
- 2
Check against breach database
We query HaveIBeenPwned's k-anonymity API — the world's largest leaked password database (850M+ breached passwords).
- 3
If leaked: change immediately
Any password showing as leaked = change it everywhere you use it. Leaked passwords are in attacker dictionaries.
What to do if your password is breached
- Change it immediately at every site where you use it
- Never reuse passwords across sites — use a password manager
- Enable 2FA on email, banking, social accounts
- Generate new passwords with our Password Generator (16+ chars, all categories)
Frequently Asked Questions
Is my password sent to anyone?
What is HaveIBeenPwned?
If my password isn't in the DB, is it safe?
My password was leaked 100 times — meaning?
Why SHA-1 and not SHA-256?
Can I test multiple passwords?
Key Takeaways
- Password Breach Checker is a free, browser-based developer tool — check if your password has been in a data breach.
- No signup, no downloads, no file uploads — your data stays on your device.
- Works on desktop, tablet, and mobile. Install as a PWA for offline access.
How to Use Password Breach Checker
- Open the tool: Launch Password Breach Checker on Toololis — no account or download needed.
- Enter your data: Paste text, enter values, or select a file directly in your browser.
- Get instant results: Everything is processed locally — results appear immediately.
- Copy or download: Save your output or share it. Bookmark for quick access next time.
Password Breach Checker — Quick Facts
- Price
- Free — no limits, no watermarks, no paywalls
- Privacy
- 100% browser-based — no data is sent to any server
- Platform
- Any modern browser on desktop, tablet, or mobile
- Category
- Developer Tools on Toololis
- Offline
- Works offline after first visit (Progressive Web App)
| Feature | Details |
|---|---|
| Tool | Password Breach Checker |
| Category | Developer |
| Signup Required | No |
| File Upload | None — processed in browser |
| Mobile Support | Fully responsive |
| Cost | Free forever |
Why Use Password Breach Checker?
You should try Password Breach Checker for a quick, private way to check if your password has been in a data breach. All processing happens in your browser. Your files and data never leave your device. According to web.dev, client-side processing is the gold standard for privacy.
On the other hand, dedicated APIs or desktop tools suit batch processing better. They also handle server-side automation. For everyday tasks, browser tools offer the best speed, privacy, and convenience.