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HomeSecurityPassword Entropy Calculator

Password Entropy Calculator

Browser-Only

Analyze password charset and calculate entropy bits from detected character types.

0 characters

Enter a password to see charset and entropy

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Frequently Asked Questions

Quick answers to common questions

What is password entropy?+

Entropy = length × log₂(charset size). It estimates how many bits of randomness a password has.

How many bits do I need?+

80+ bits is reasonable for most accounts. 128+ bits is excellent.

How is charset detected?+

We inspect your password for lowercase, uppercase, digits, and symbols, then sum the pool sizes of each type present.

Is this stored?+

No. All calculations run in your browser.

Processing runs in your browser. Your inputs are not sent to our servers.