JSON formatter & validator
Format, beautify, validate, and minify JSON online. Pinpoint syntax errors by line and column, sort keys, and copy or download the result.
Password strength checker
Check password strength and crack time privately in your browser. Spots common words and patterns, with an optional breach check.
Checked entirely in your browser. Nothing is sent or stored.
How to use Password strength checker
Test how strong a password is and how long it would take to crack.
- Detects common passwords, dictionary words (including letter swaps like p@ssw0rd), keyboard sequences, repeats, and years
- Estimates crack time for online attacks, slow password hashes, and fast offline attacks
- Optional breach check against Have I Been Pwned. Only the first 5 characters of the password's SHA-1 hash leave your device
The strength check runs entirely in your browser. For new passwords, use the password generator.
Password strength checker FAQs
Is Password strength checker free?
Password strength checker is a free online tool on ReallyUseful.Tools. No account is required.
Does Password strength checker run in my browser?
Password strength checker is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.
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