Password Generator

Generated 2 password(s) of 16 character(s) from a pool of 87 symbols (103 bits of entropy).

How it works

• Read the requested length, character classes and count.
• Built the character pool from the selected classes.
• Drew each character from the pool with rejection sampling over the random bytes.
• Reported the true pool size and the resulting entropy in bits.

• A seed was supplied for a reproducible example; production generation uses the platform CSPRNG.
• This tool generates secrets in your browser and never sends, logs or stores them.

Methodology

1. Build the character pool from the selected classes, optionally removing visually ambiguous characters.
2. Draw characters from the platform CSPRNG; for a seeded example, derive bytes from a deterministic PRNG instead.
3. When requested, place one character from each selected class and shuffle with the same random source so the guarantee does not bias the remaining positions.
4. Report the pool size, the password length and the Shannon-style entropy estimate length × log2(poolSize).

Usage

1. Choose the password length (8 to 256 characters).
2. Select the character classes to include and whether to avoid ambiguous characters.
3. Generate one or more passwords and copy the value you need.

Examples

These are examples, not current values: they use fixed inputs, while the interactive tool computes live results in your browser.

Two reproducible 16-character passwords

{
  "length": 16,
  "count": 2,
  "seed": "example"
}

Alphanumeric only, no ambiguous characters

{
  "length": 20,
  "symbols": false,
  "excludeAmbiguous": true,
  "seed": "example"
}

Guarantee one of each class

{
  "length": 24,
  "requireEachClass": true,
  "seed": "example"
}

Limitations

Why length beats complexity rules

Modern guidance (NIST SP 800-63B) de-emphasises forced symbol and rotation rules and favours long, random, unique secrets. This generator lets you choose a long random password and guarantees class coverage only when a site requires it.

The entropy figure is honest about what randomness alone contributes. It is not a guarantee about the rest of your account security, which depends on how the service stores and checks the password.

A seed is not a feature for real secrets

The seed option exists so the documentation example and the automated tests are reproducible. A seeded password is predictable and must never be used as a credential. Without a seed, generation uses the platform CSPRNG.