Password Strength Checker

Analyze your password's strength, entropy, and estimated crack time. 100% client-side — nothing is sent to any server.

Password
Requirements
12+ characters
Uppercase (A-Z)
Lowercase (a-z)
Numbers (0-9)
Special chars (!@#)
Not common
No repeats (aaa)
Generator
Length16
Password Strength

Enter a Password

Type above to begin

Crack Time

Entropy

0.0 bits

Length

0chars

Unique Chars

0

Char Types

0of 4
Documentation

How It Works

We calculate entropy (randomness) based on character types and length. Higher entropy means more possible combinations, making the password harder to crack.

Your password never leaves your browser. All analysis is done client-side.

Password Best Practices

  • Use a unique password for every account.
  • Use a password manager to store them safely.
  • Enable two-factor authentication (2FA) whenever possible.
  • Passphrases (e.g., "correct-horse-battery-staple") are both strong and memorable.

Entropy Formula

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H = Entropy (bits), L = Password length, N = Charset size

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Frequently Asked Questions
How to Use

About the Password Strength Checker

What it calculates

This password strength checker provides quick everyday calculations for tips, discounts, passwords, and daily tasks. Analyze password strength, entropy, and crack time.

When to use it

Use whenever you need a fast answer without opening a spreadsheet.

Example

Adjust the inputs above to model your specific scenario with the Password Strength Checker.

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