Password Entropy

Check password length, character variety, and obvious repeated or common patterns locally. The bit count is an upper bound, not measured entropy.

100% Client-Side / Offline Buy me a coffee
Input
Ready
Output
Ready

How It Works

Type a password to calculate its character pool size, entropy in bits, NIST strength tier, and theoretical brute-force combinations.

Frequently Asked Questions

Is my data private and secure?

Yes. All operations run 100% inside your local web browser runtime using client-side JavaScript. No text, tokens, code, or personal data are ever uploaded to an external server or cloud service.

Can I run this tool completely offline?

Yes. You can install the packaged Manifest V3 Chrome Extension version from GitHub or save this standalone HTML page locally to use without an internet connection.

Is this tool free and open source?

Yes, all tools are 100% free and licensed under the permissive MIT license. If this tool helped you solve an annoyance, you can support development at ko-fi.com/jju1s.