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Secure Password Generator

Free, strong password generator — any length from 10 to 20+ characters, fully offline.

Strength
Weak · 0 bits
Quick length
Character sets

Generate strong passwords that you can actually use

A good password generator produces passwords that are both cryptographically random (so they cannot be guessed) and practically usable (so you will actually adopt them). This tool uses crypto.getRandomValues() — the browser’s secure random source — to produce passwords you can trust.

What makes a password strong?

Password strength is measured in bits of entropy — essentially, the logarithm of the number of passwords an attacker would have to try. A 12-character password using lowercase, uppercase, digits and symbols has around 78 bits of entropy, which is unbreakable by brute force today.

Length matters more than complexity. An all-lowercase 20-character password has similar strength to a 12-character mixed-case one, and is far easier to remember if you ever need to.

Custom rules

  • Length — anywhere from 4 to 64 characters. Common picks: 10 (minimum for modern accounts), 12 (balance of usability and strength), 14 (recommended default for most accounts), 16 or 20 for high-value accounts. The default is 20 (~130 bits of entropy with all sets). Preset chips above the slider cover the common lengths in one tap.
  • Character sets — turn off any category a website prohibits.
  • Exclude ambiguous characters — useful for passwords you will handle physically.

Where to store what you generate

Paste the output directly into a password manager (Bitwarden, 1Password, KeePassXC, iCloud Keychain, etc.). Reusing passwords is still the single biggest hole in personal security — a generator only helps if you pair it with a password manager.

Frequently asked questions

What password length should I pick?
**10 characters** is the practical minimum for a modern account — still breakable by a determined attacker but adequate for low-value sites. **12** is a reasonable default, **14** is the sweet spot for most accounts (roughly 90 bits of entropy with mixed sets), and **16 or 20+** is right for email, banking, and your password-manager master password. If in doubt, go longer — adding characters is the cheapest way to make a password stronger.
How strong is "strong enough"?
For most online accounts, a 14-character password drawing from lowercase, uppercase, digits and symbols gives roughly 90 bits of entropy — more than enough to resist any practical brute-force attack. For high-value accounts (email, banking, password manager master), go to 20+ characters.
Should I include symbols?
Yes, if the site accepts them. Symbols significantly increase the character-set size and therefore the entropy per character. If a site rejects symbols, increase the length to compensate.
Why exclude ambiguous characters?
Characters like 0, O, 1, l, I and the vertical bar can be hard to distinguish in some fonts. Excluding them makes a password you can read aloud or hand-type reliably, at a small cost to entropy.
Is this password generator really free?
Yes — no signup, no ads inside the tool, no length cap behind a paywall. The generator runs entirely in your browser using `crypto.getRandomValues()`, so we never see your passwords and there's nothing for us to charge for.