Password Generator
Generate strong, random passwords with custom length and character sets. Calculate password entropy and strength instantly.
chars
Generated Password
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Strength —
Entropy (bits) —
How to Use This Calculator
- Set the desired Password Length.
- Choose which character sets to include: uppercase, numbers, symbols.
- Click to generate — each click produces a new random password.
- Copy the password and store it in a password manager.
Formula
Entropy (bits) = Length × log₂(Character Set Size)
A 16-char password with all sets (~95 chars) has ~105 bits of entropy.
Example
Length 16, all character sets enabled (95 possible characters).
- Entropy = 16 × log₂(95) = 16 × 6.57 ≈ 105 bits
- Strength: Very Strong
Frequently Asked Questions
- A strong password is long (12+ characters), random, and uses a mix of uppercase, lowercase, numbers, and symbols. Avoid dictionary words, names, and predictable patterns.
- Entropy measures how unpredictable a password is, in bits. Higher entropy means harder to crack. 60+ bits is considered strong for most uses; 80+ bits is very strong.
- Yes. Passwords are generated entirely in your browser using Math.random() and are never sent to a server. For extra security, use your browser's built-in password manager.
- At least 12 characters for most accounts. For sensitive accounts (banking, email), use 16–20+ characters with all character types enabled.