Random Password Generator

What is a random password generator?

A random password generator picks characters at random from an alphabet you choose. It does not remember accounts and does not hash anything. You copy the result into a password manager or a signup form.

This one draws its characters with cryptographically secure randomness.

Random password generator options

Length

4 through 4096 characters. Default 20.

Count

1 through 1000 passwords, one per line. Default 1.

Lowercase, uppercase, digits, symbols

All on by default. Symbols are a fixed set of 25: !@#$%^&*()-_=+[]{};:,.<>?

Exclude ambiguous

Off by default. Turn it on to drop 0, O, o, l, 1, I and |.

Require each class

Off by default. Turn it on to demand at least one character from every enabled class. Each password gets up to 10,000 attempts, and the tool refuses rather than loop forever.

Custom alphabet

Optional. When set, passwords use only those characters, up to 1,024 unique ones, and at least two. The class switches, exclude ambiguous and require each class cannot be combined with it.

• Total output is capped at 1 MiB.

The result shows the passwords, how many were made, and the alphabet size, so you can work out the strength yourself.

Why not type a password yourself

People reuse short passwords, and those passwords end up in breach lists. A long random string avoids both the reuse and the pattern that only looks random, such as a keyboard walk.

Strength comes from length and alphabet size. With every class on, the alphabet has 87 characters, so the default 20 characters give about 129 bits of randomness. Brute force will not get through that.

A website's generate button may quietly drop symbols, cap the length at 16, or use Math.random. You cannot check that from the page. This one states the alphabet, the length and the kind of randomness it uses.

Random password generator alternatives

Password managers such as Bitwarden and 1Password generate and store passwords in one step. Use one of those for your own accounts, because a password you cannot find again is not much use.

Argon2id Hash Generator hashes a password you already have, for storing a verifier rather than making a new secret.

Things to know about random passwords

The symbol set is fixed, so two runs with the same settings use the same alphabet. If a site rejects some symbols, type the letters, digits and symbols it does accept into custom alphabet.

Exclude ambiguous helps when someone will read the password off a screen or over the phone. It shrinks the alphabet a little, which is the trade.

Characters are drawn uniformly from the unique characters you allow. Repeats in a custom alphabet are ignored, so aabbcc is an alphabet of three.