Password Strength Tester
Test password strength with entropy calculation, time-to-crack estimate (against modern GPU attack), and issue detection — too short, no symbols, common password, repeated characters, sequences.
What powers the Password Strength Tester
Entropy calculation (charset × length)
Time-to-crack estimate at 10^11 guesses/sec (modern GPU)
5-level strength grade (Very weak → Very strong)
Issue detection: length, casing, digits, symbols, common passwords, repeats, sequences
password never sent
Why the Password Strength Tester is different
Browser-native
The Password Strength Tester runs entirely in your browser. Input is processed locally — never uploaded, never logged, never cached anywhere outside your device.
No artificial limits
No daily quotas, no character ceilings, no "upgrade for more" walls. Every feature is the complete feature — the same on the first use as the thousandth.
Production-grade quality
Built to the same engineering bar as paid SaaS tools — accurate algorithms, audited logic, responsive design and accessibility-tested interactions.
Common use contexts
- Choosing a strong master password
- Auditing existing passwords for weakness
- Education — understanding what makes a password strong
- Comparing passphrase vs random-string strength
Private and secure
Zero upload
All processing happens in your browser. Input is never transmitted, logged or cached.
Works offline
Once the page loads, the tool runs without an internet connection. No network calls happen during use.
No tracking
No accounts, no cookies for tool state. Only aggregate analytics count visits at the page level.