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ErgaLab
Generators

Password Generator

Adjust the length and character sets, then generate a random password with a live entropy estimate — nothing is stored or transmitted.

Options

Length20

Generated password

Very strong
HNh1]}8fS%v2)cPBL8L!

~129 bits of entropy from a 87-character set.

How it works

Every character is chosen using crypto.getRandomValues, the browser's cryptographically secure random number generator, with rejection sampling to guarantee every allowed character is equally likely — a naive random % charsetLength approach would subtly favor some characters over others.

The strength label is based on entropy — the total number of equally likely passwords a given length and character set could produce, expressed as bits. Longer passwords and larger character sets (especially adding symbols) increase entropy far more than you might expect, since it grows multiplicatively with each additional character.

Examples

Strong general-purpose password

20 characters, all sets.

xQ7!mZ2@vR9#pL4$wK1&

Numbers only PIN

For numeric-only fields.

48213096

No ambiguous characters

Easier to type from a screen.

aB7cD9eFgH2jK4mN6pQr

Frequently asked questions