Password Strength Analyser

Type a password above

Entropy

0 bits

Est. Crack Time

-

Character Set Size

0

How to use this password strength analyser

  1. Type a password into the box — nothing is sent anywhere, it all happens on your device.
  2. Watch the bar and label update in real time as you type, from "Very weak" to "Very strong".
  3. Check the entropy and estimated crack time to understand exactly why a password is weak or strong.

How is this calculated?

Entropy is estimated as log2(character_set_size ^ length), a standard measure of how many guesses a brute-force attacker would need. Crack time assumes 10 billion guesses per second, a realistic rate for offline attacks against weakly-hashed passwords.

Is my password sent anywhere?

No — everything is calculated locally in your browser and never transmitted or stored.

What makes a password actually strong?

Length matters more than complexity — a 16-character passphrase is usually stronger than an 8-character password full of symbols. Aim for at least 12-16 characters.

Is crack time an exact prediction?

No, it's a mathematical estimate assuming a brute-force attack at a fixed guess rate. Real attacks may be faster or slower depending on hardware and the hashing algorithm used to store the password.