Useful Utilities

Password Generator

Random passwords from a cryptographic source, with the character sets, look-alike and exclusion filters you choose, plus the entropy and crack-time maths.

Fill in the values and calculate

Password lengthDefault 16
How many to generateDefault 1
Use lowercase lettersDefault true
Use uppercase lettersDefault true
Use digitsDefault true
Use symbolsDefault true
Avoid look-alikesRemoves I l 1 O 0 and | from the mixDefault false
Characters to excludeLeave blank unless a client forbids specific charactersDefault

The form sends itself back to this page — results print below, computed on the server.

No results yet: fill the form above and press Calculate.

About Password Generator

Every character comes from a cryptographic draw over the exact pool your settings allow, and each password is guaranteed to contain at least one character from every set you turned on.

The page prints the pool size, the entropy as an explicit length x log2(pool) sum in the notes, and the brute-force crack time, so you can check the numbers against the character counts instead of trusting a badge.

Questions about Password Generator

Why guarantee one character from every set?

A purely random draw can silently skip a whole set, which weakens some passwords in the batch. Guaranteeing one keeps every password valid at a cost of at most a few bits.

Is length or a bigger symbol pool better?

Per character both add log2(pool) bits, and adding characters is the easier habit to keep: two more characters usually outweigh symbol tricks.

Can I exclude characters the site rejects?

Yes, the exclude field removes exactly the characters you type before anything is drawn, and the entropy is recomputed on the smaller pool.

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