What makes a password strong?

Strength comes from entropy, the number of possible combinations. A 24-character password using all character types has roughly 153 bits of entropy, making it effectively impossible to crack with current technology.

What do the Weak, Fair, Strong and Very strong labels mean?

The meter labels a password by its entropy: under 40 bits is Weak, 40 up to 60 bits is Fair, 60 up to 80 bits is Strong, and 80 bits or more is Very strong. The default here, 24 characters of all four types, is about 153 bits.

How is the entropy calculated?

Entropy in bits = password length × log2(character set size). For a 24-character password using all 84 characters this tool offers (26 uppercase, 26 lowercase, 10 digits and 22 symbols), that is 24 × log2(84) ≈ 153 bits.

Should I store the password in a password manager?

Yes. This is the recommended approach. Generate a unique, random password for every account and save it in a password manager.

Strong password generator

Generate high-entropy passwords with a strength indicator showing the exact bit count. A strong password is long, uses all character types, and is unique to every account. This tool creates all three in your browser.

Very strong · 153 bits

Copying puts the password on your clipboard. Your operating system may keep it in its clipboard history.

Length24

A–Z uppercasea–z lowercase0–9 numbers!@# symbols

Bulk generation

Generatepasswords

How it works

The tool uses crypto.getRandomValues(), the browser's built-in cryptographically secure random number generator, to select characters or words. No library is required and our servers are not involved. The password is generated entirely inside your browser tab.

Processing runs in your browser

All generation runs locally in your browser. The password exists only in your browser until you copy it. You can prove this yourself in your browser's DevTools Network tab. Once you copy a password, your operating system may keep it in its clipboard history or sync it to your other devices: Windows clipboard history and cloud clipboard, Apple Universal Clipboard or a clipboard manager. In a private window, Chrome, Edge and Firefox keep copies out of Windows clipboard history and cloud clipboard.

Related operations

To share a Wi-Fi password without reading it out, use the Wi-Fi QR code generator. When you need random identifiers rather than secrets, use the UUID generator. To check that a copied key or file arrived unchanged, compare SHA-256 checksums with the hash generator.

Frequently asked questions

What makes a password strong?: Strength comes from entropy, the number of possible combinations. A 24-character password using all character types has roughly 153 bits of entropy, making it effectively impossible to crack with current technology.
What do the Weak, Fair, Strong and Very strong labels mean?: The meter labels a password by its entropy: under 40 bits is Weak, 40 up to 60 bits is Fair, 60 up to 80 bits is Strong, and 80 bits or more is Very strong. The default here, 24 characters of all four types, is about 153 bits.
How is the entropy calculated?: Entropy in bits = password length × log2(character set size). For a 24-character password using all 84 characters this tool offers (26 uppercase, 26 lowercase, 10 digits and 22 symbols), that is 24 × log2(84) ≈ 153 bits.
Should I store the password in a password manager?: Yes. This is the recommended approach. Generate a unique, random password for every account and save it in a password manager.

Last reviewed September 30, 2026

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