Password Generator

Generate strong random passwords or memorable passphrases with strength meter, entropy, and crack-time analysis.

Password settings

Updates as you type

Mode

Output type ?

Length & character pool

Length —

8
weak 12
ok 16
good 24
strong 32+
overkill

Character sets ? —

Output

Quantity ? —

151020

Advanced options (optional)

Exclude ambiguous characters Removes 0 O 1 l I so generated passwords read cleanly when printed or dictated.

Require at least one of each selected set Prevents quirks like a 16-character "strong" password that happens to contain only lowercase letters.

No repeating characters Best-effort: only meaningful when length ≤ pool size. Reduces entropy slightly.

Generated password

Entropy

— bits

Crack time

—

Pool size

— chars

Strength breakdown

—

Length

—

Character pool

—

Entropy

—

Combinations

—

Longer is stronger. 16+ characters with mixed sets pushes entropy past 100 bits — comfortably beyond anything guessable in a human lifetime at today's hardware.

How we generate

Passwords are built with crypto.getRandomValues() locally in your browser — they never touch our servers. We only remember your settings (length, sets, mode) via the shareable link, never the passwords themselves.

How password strength is measured

E = log₂(N) × L

E: Entropy, measured in bits — how many guesses an attacker would need in the worst case
N: Size of the character pool (or word list, for passphrases)
L: Length of the password in characters (or words, for passphrases)

Worked example — your settings

Pool size N = —
Per-character entropy = log₂(N) = — bits
Length L = —
Total entropy E = — bits
Combinations = 2^E = —
Brute-force time @ 1 trillion guesses/sec = —

Real attackers target the weakest link — reused passwords and breached databases — not individual hashes. Aim for ≥ 80 bits of entropy for anything valuable, use a different password per site, and store them in a password manager. Entropy above ~100 bits is well past the point where brute force is the limiting factor; the formula keeps growing, but the practical gains are marginal.

Password settings

How password strength is measured

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