Passphrase Strength Validator
Rate passphrase security by entropy.
Check passphrase strength and entropy instantly. Free passphrase strength checker with entropy estimate.
Calculator Inputs
About Passphrase
Rate passphrase security by entropy.
Entropy-based score rewarding long multi-word phrases.
Where it is used
Throwaway security, teaching secure passphrases.
How to use the Passphrase
- Passphrase — enter the value (e.g. blue whale jumps over sun).
- Calculate — press the Calculate button to see the result instantly above.
Formula
Length × log2(character pool) ≈ entropy bits; word count bonus.
Examples
Example
passphrase:blue whale jumps over sun
Result: 5 words, 25 chars — STRONG ✓
Frequently Asked Questions
- Passphrase vs password?
- Long phrases are easier to remember and stronger than short random passwords.