Cryptographic Password Entropy Checker
Calculate exact mathematical entropy bits and attack complexity for passwords.
Runs entirely in your browser — your data is never uploaded to any server.
How it works
- Enter passwordType string
- Calculate pool sizePool R and length L
- Read entropyBits score
What this tool does
- E = L * log2(R) formula
- Pool size breakdown
- Zero server storage
Frequently Asked Questions
60+ bits is considered good; 80+ bits is cryptographically strong.
Privacy and security
Your input is processed by JavaScript running inside your browser. Nothing you paste is sent over the network, logged, or stored — which is what makes this safe to use with production data. If you want to check this yourself: open your browser’s developer tools, switch to the Network tab, and use the tool — you will see no request carrying your file or input leave the page.