tooloora

Password Generator — passwords & passphrases, local

Create strong random passwords or memorable passphrases from the EFF wordlist, with a live entropy meter — generated in your browser, never sent anywhere.

Runs locally — nothing is uploaded

Very strong102 bits of entropy

Runs entirely on your device — nothing is sent and generated passwords are never stored.

What this password generator does

This tool creates strong random passwords and memorable passphrases right in your browser. Pick character classes and length, or switch to passphrase mode and string together random words from the EFF wordlist. A live entropy meter shows how hard the result would be to guess, and a single click copies it to your clipboard.

Why random passwords matter

The most common way accounts get compromised is reused or guessable passwords. If one service leaks your password and you used it elsewhere, attackers try it everywhere. A long, random, unique password per account removes that risk — and a generator is the only practical way to create one you would never invent yourself.

How the strength meter works

Strength is measured in bits of entropy, an estimate of how many guesses an attacker would need. Each extra character and each extra character type multiplies the possibilities:

EntropyRatingRough meaning
under 40 bitsweakcrackable quickly
40–60 bitsfairokay for low-value logins
60–80 bitsstronggood for most accounts
80+ bitsvery strongsuitable for high-value accounts

The fastest way to raise entropy is length: a longer password beats a short one with more symbol types almost every time.

Password or passphrase — which should you pick?

A passphrase strings together randomly chosen words: acorn.tiger.bonus.cider.wolf. The principle is called Diceware, and the words here come from the EFF short wordlist published by the Electronic Frontier Foundation in its 2016 article “Deep Dive: EFF's New Wordlists for Random Passphrases” — 1,296 words (6⁴, four dice rolls), each at most five characters, curated for memorability and published under CC BY 3.0. Every uniformly drawn word contributes log₂(1296) ≈ 10.3 bits of entropy, so five words reach about 52 bits and seven about 72 — the meter shows the exact figure, calculated the same honest way as in character mode.

Pick a passphrase when you have to memorize or type the secret yourself: a master password, a Wi-Fi key, disk encryption. Pick a random character password for everything that lives in a password manager anyway. One honest limitation: the wordlist is English only, because the EFF documents its curation and license while we found no German list with comparable provenance — random selection, not the words' language, is what makes a passphrase strong. Capitalizing the words is pure readability and adds no entropy, so the meter does not count it; the optional trailing digit is drawn randomly and honestly adds just over 3 bits — no more, because its position is fixed.

Secure by design

Passwords and passphrases are generated with your browser's cryptographic random number generator (crypto.getRandomValues) using rejection sampling, so there is no statistical bias toward certain characters or words. Nothing is sent to a server, nothing is logged, and generated passwords are never stored — only your preferences (mode, length, character sets, word count) are remembered locally.

Tips for everyday use

  • Use a unique password for every account — never recycle one.
  • Store them in a password manager so you do not have to remember them.
  • Turn on two-factor authentication wherever it is offered.
  • Exclude ambiguous characters (l, I, 1, O, 0) if you will read or type the password by hand.
  • For passphrases you must memorize, prefer length over complexity.

Frequently asked questions

Are the passwords generated securely?

Yes. They use your browser's cryptographic random number generator (Web Crypto, crypto.getRandomValues) with rejection sampling, so every character is uniformly random with no bias. Generation happens entirely on your device.

Is my password sent anywhere?

No. Nothing leaves your browser — there is no server call, no logging and no storage of generated passwords or passphrases. Only your option choices (mode, length, character sets, word count) are remembered locally so the tool opens the way you left it.

What is entropy and how strong is strong enough?

Entropy, measured in bits, estimates how hard a password is to guess: more bits means exponentially more combinations. As a rule of thumb, under 40 bits is weak, 60–80 bits is strong, and 80+ bits is very strong. Increase length and enable more character types to raise it.

Why exclude ambiguous characters?

Characters like l, I, 1, O, 0 and o look alike in many fonts and are easy to mistype when reading a password aloud or off a screen. Excluding them helps for printed or dictated passwords — at a small cost to the character pool.

How long should my password be?

For most accounts 16 characters with mixed types is plenty. For high-value accounts use 20 or more, and always combine a unique password with a password manager and two-factor authentication.

What is a passphrase, and when is it the better choice?

A passphrase strings together randomly chosen words — the Diceware principle. This tool draws them uniformly from the EFF short wordlist (1,296 words, so each word adds about 10.3 bits of entropy). Passphrases shine wherever you must remember or type the secret yourself: a master password, a Wi-Fi key, a disk encryption phrase. For accounts stored in a password manager, random character passwords are just as good.

Why are the passphrase words in English only?

The EFF documents how its list was curated (common, memorable words of at most five characters, no confusing pairs) and publishes it under a clear license. We found no German list with comparably documented curation and licensing — rather than embed an unvetted list, the passphrase mode honestly stays English. Its security comes from random selection, not from the words' language.