Password Strength — Free, Private & Offline
Password Strength Checker free, online and 100% offline — check entropy and crack-time with zxcvbn. Private & secure: your input is processed in your browser and never sent to a server. No sign-up.
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What is Password Strength?
Password Strength Checker uses zxcvbn to estimate how long it would take an attacker to crack your password under different scenarios. Analysis runs locally - your password is never transmitted.
How to use Password Strength
- Open Password Strength — it loads instantly and runs entirely in your browser.
- Paste or type your input. It is processed locally and never transmitted.
- Adjust the available options to match exactly what you need.
- Get your result — private, offline and free.
Use cases
- Free, offline password strength checker for secrets, tokens or proprietary code you don't want to paste into a remote server.
- Work with sensitive material privately on locked-down or air-gapped devices.
- Quick one-off password strength checker when you just want a result without signing up or paying.
- High-volume work where a cloud SaaS would be slow, costly or non-compliant.
Frequently asked questions
Is Password Strength free?
Yes — Password Strength is completely free with no paywall, trials or usage caps. Every TabTasker tool is free forever.
Does Password Strength work offline and keep my data private?
Yes. Password Strength runs 100% client-side in your browser. Your input never leaves the page — nothing is sent to a server — and it keeps working offline once loaded.
Is this password strength checker better than online tools that send my data to a server?
For privacy, yes. Most online password strength checker tools transmit whatever you paste to their backend. TabTasker processes everything locally, so sensitive input never leaves your browser.
Do I need to create an account or install anything?
No. No account, no extension and no install — just open the page and start. It works on any modern browser, desktop or mobile.