Password strength checker
Test a password’s strength: entropy and estimated crack time, 100% in your browser.
Nothing is sent: everything is computed in your browser.
🔒 100% client-side — no data sent
Measure how strong a password is by calculating its entropy and an estimate of how long it would take to crack. Everything runs 100% in your browser, so your password is never sent to any server.
What is it for?
- ▸ Check whether a password is strong enough before signing up somewhere
- ▸ Compare several variants to pick the most resistant one
- ▸ Teach a team about good password security habits
- ▸ Audit password quality against an internal security policy
FAQ
Is my password sent over the internet?
No. The analysis runs locally in your browser and no character is ever transmitted to a server.
What is password entropy?
It is a measure in bits of how unpredictable a password is: the higher the entropy, the harder it is to guess by brute force.
Is the displayed crack time accurate?
It is an estimate based on assumed attack speeds. It gives an order of magnitude, not an absolute guarantee.
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