BYTETOOLS

Password Generator

Generate strong random passwords with cryptographically secure randomness. Choose length and character sets, see entropy strength, copy instantly.

16
StrengthVery strong · 104 bits of entropy

What is the Password Generator?

The ByteTools Password Generator creates strong, unpredictable passwords using your browser's cryptographically secure random number generator (crypto.

  • Cryptographically secure randomness (crypto.getRandomValues)
  • Length from 4 to 128 characters
  • Lowercase, uppercase, digits and symbols toggles
  • Exclude ambiguous characters option (0 O 1 l I)
  • Entropy-based strength meter in bits
  • Generate multiple passwords and copy with one click

How to use the Password Generator

  1. 1

    Set the password length with the slider (12–20 characters is a good default).

  2. 2

    Tick the character sets to include: lowercase, uppercase, digits, symbols.

  3. 3

    Optionally exclude ambiguous characters like 0/O and 1/l/I.

  4. 4

    Click Generate, check the strength meter, and copy the password.

  5. 5

    Need several? Set a count and generate a whole list at once.

About the Password Generator

The ByteTools Password Generator creates strong, unpredictable passwords using your browser's cryptographically secure random number generator (crypto.getRandomValues) — the same class of randomness used by password managers. Choose a length from 4 to 128 characters and mix lowercase, uppercase, digits and symbols.

A live strength meter shows the entropy of your settings in bits so you can see exactly how hard the password would be to brute-force. An option to exclude ambiguous characters (0, O, 1, l, I) makes passwords easier to read aloud or type from paper, and you can generate a whole batch at once.

Passwords are generated entirely on your device and never sent, stored or logged. Nothing leaves the page, so what you generate here is known only to you.

Frequently asked questions

Are random password generators safe to use?

A browser-based generator like this one is safe because it runs entirely on your device using the Web Crypto API — the password is never transmitted or stored. Avoid generators that create passwords on a server, since you cannot verify what happens to them.

How long should a strong password be?

Aim for at least 12–16 characters with mixed character sets, which gives roughly 78–104 bits of entropy — far beyond practical brute-force attacks. For master passwords or encryption keys, 20+ characters is a sensible margin.

What does the entropy strength meter mean?

Entropy measures unpredictability in bits: each extra bit doubles the number of guesses an attacker needs. It is calculated as length × log2(pool size), so a 16-character password from a 94-character pool has about 105 bits — effectively uncrackable today.

Why exclude ambiguous characters like 0 and O?

In many fonts 0/O and 1/l/I look identical, which causes errors when a password is read from paper, dictated over the phone or typed on a TV keyboard. Excluding them slightly reduces entropy but greatly improves usability — just add a character or two of length to compensate.

Is it better to use a password manager?

Yes — generate a unique password here or in a manager, but always store it in a reputable password manager rather than reusing it. Unique-per-site passwords are the single biggest defence against credential-stuffing attacks.

Does this tool store or send my generated passwords?

No. Generation happens in your browser's memory using JavaScript and the Web Crypto API. Nothing is logged, cached or transmitted, and refreshing the page destroys everything.

Guides for Password Generator

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