Passphrase Generator

Create cryptographically random passwords and passphrases locally in your browser.

Private by design: Web Crypto only, no network submission.

Choose a format

Number of words

This compact local word list needs more words than a Diceware list.

Separator

Capitalize

Advanced and batch settings

Results

Suffix digits

Prevent duplicate batch rowsAdd a random numeric suffix

Generated secret

Strong · 84.0 bits

Local only

Choose valid settings to generate a result.

Result

0passphrases

12 words from a 128-word local list. Entropy reflects the generator's actual selection space.

Use it safely

Use a unique password for every account and store it in a password manager.
Enable multi-factor authentication where available.
Clipboard contents may remain available to other apps after copying.

How the strength estimate works

Entropy is calculated from this generator's valid output space. Under an illustrative offline attack averaging 10 billion guesses per second, the midpoint search time is about 30.7 million years. Real risk depends on server hashing, breaches, reuse, phishing, and account protections; this is not a breach prediction.

Flow

Select one or more character classes.
Sample the full password with Web Crypto.
Reject and resample only when a selected class is missing.
Calculate entropy from the same valid output space used by generation.

Example

Worked example: 20-character password

1 Choose the Recommended 20 preset.
2 The tool samples locally until every selected character class is present.
3 Copy the masked result into your password manager without needing to reveal it.

A unique 20-character password is generated with Web Crypto and no server submission.

How

Choose Random password or Passphrase.
Use the recommended preset or adjust length and allowed characters.
Copy the result directly into a password manager, then clear the generated secret.

Cases

Create a unique password for a personal or work account.
Generate a long secret for a password manager.
Produce private test credentials or a local batch for QA.

Avoid

Selecting no character classes before generation.
Using fewer than 15 characters for a password that is the only authentication factor.
Reusing a generated password across accounts or leaving it in clipboard history.

FAQ

How long should a generated password be?

For a password used as a single authentication factor, current NIST guidance sets a 15-character minimum. Longer unique passwords remain safer, especially when a site limits character variety.

Does the generator guarantee selected character classes?

Yes. It uses rejection sampling so every accepted password contains each selected class while remaining uniform across the valid output space.

Are generated passwords stored or sent to a server?

No. Generation runs locally with Web Crypto, output is masked by default, and this tool does not add generated secrets to its result-history component.

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Passphrase Generator