Password Strength Checker

The Password Strength Checker estimates how strong a password is by calculating its entropy in bits from the size of the character set and the length, then translating that figure into an estimated crack time and concrete, actionable suggestions for improvement. You see straight away whether a candidate password is genuinely robust or only looks complex.

It helps anyone choosing a password for an important account understand why length usually matters more than sprinkling in a few symbols, and exactly where a given password falls short. Seeing the entropy expressed as a number makes the difference between a weak and a strong password tangible rather than abstract.

Analysis is performed entirely in your browser — your password is never transmitted or stored — so it is completely safe to test the real values you intend to use. With no install and no account, you can pair it with the password generator to confirm that a freshly generated secret is strong enough for the job.