How it works : Passphrase
Six random words beat an eight-character password, and the tool PROVES it by the arithmetic. It also says what is useless: the capital and the separator are worth zero bits.
A password generator is the worst possible place to trust a server. If the secret is built anywhere but on your machine, somebody else has seen it go past, and you have no way of knowing whether they kept it. Here the phrase is drawn inside your browser, with your system's random generator, and it disappears when you close the tab.
The method is the dice one: every word is drawn independently from a list of 7,776 words, because 7,776 is exactly the number of outcomes of five dice. That is not a programmer's trick, it is a method you can redo by hand with real dice and the printed list, and that is what makes it verifiable.
What this tool does and “password strength” meters never do: it shows the arithmetic. Every line says how much it contributes, and the lines that contribute NOTHING are written as zero. Putting a capital at the start of each word does not make a phrase stronger by a single bit, because it is a rule everyone knows. Saying so is more useful than a green bar.
How it works
- Set the number of words. Six is the right choice for almost everybody.
- Click “Build a passphrase”. It appears, with its entropy worked out line by line and the time it would take to find it.
- Copy it and store it straight away, in a password manager or in your head. It exists nowhere else: nobody can give it back to you.
Formats accepted
This tool receives nothing at all: no file, no text. So there is nothing to send, even by mistake. It is the only tool in the workshop in that position, and it is why its trust banner talks about what it BUILDS rather than what you drop in.
No input
The tool starts from your settings and your system's random generator. The word list is embedded in its code: there is nothing to fetch, and the tool works with the connection cut.
Its limits
Two lists of 7,776 words, one per language, and not one more
We only embed a list if its free licence is written down in black and white by its author, and we had to rule several out for that reason alone: one widely circulated French list has no findable licence, another has an author who writes that he himself does not know which one applies. The two you have here are the Electronic Frontier Foundation's, under a Creative Commons Attribution licence, and the one compiled by “Tango” for Tails OS and The Tor Project, under CC0 1.0 Universal. Neither contains accented characters, which is deliberate: a word you cannot type is not a usable word.
The capital and the separator add NOTHING, and the tool shows them as zero
They are deterministic rules: someone who knows how this tool works already knows them. So they do not multiply the number of phrases to try. They are there only because some forms demand a capital or refuse spaces, and the tool shows them honestly as zero bits rather than inflating a counter.
Four words in the list already contain a hyphen
They are drop-down, felt-tip, t-shirt and yo-yo. If you choose the hyphen as a separator, the resulting phrase no longer splits apart by eye. It changes nothing about its strength, but it can be surprising on re-reading, so we say it.
A lost phrase is lost
It is sent nowhere, written nowhere, and it disappears when the tab closes. That is exactly the property you want from a secret generator, and it means backing it up is your job, not ours.
Attack times are orders of magnitude, with the assumption shown
They depend entirely on how the service holding your password protects it, and that is invisible to you. We give three named assumptions rather than a single figure that would look like a guarantee. All of them assume the attacker knows the method: that is Kerckhoffs's principle, and the only honest assumption.
Questions about this tool
Is the phrase sent anywhere?
No, and this is the tool where that matters most. Open the inspector with the F12 key, “Network” tab, clear the list, then build as many phrases as you like: the list stays empty. Cut your connection and do it again: the tool still builds, because the word list is in its code. A secret generator that needed the network would be a shared-secret generator.
Why six words rather than a complicated eight-character password?
Because six random words are about 77 bits of entropy, and eight characters drawn TRULY at random from a keyboard are about 52. Six words are therefore more than thirty thousand times harder to find, and infinitely easier to remember. And an eight-character password chosen by a human, with its capital at the front and its digit at the end, is worth far less than 52 bits: that is precisely the pattern attack tools try first.
Where does the number 7,776 come from?
From five dice. Six faces to the power of five is 7,776, so every word in the list corresponds to one throw of five dice, and the method can be redone by hand with real dice and the printed list. That is what makes it verifiable by anybody, without trusting a program, including ours.
Why is the capital shown as zero bits?
Because it adds no possibility to try. If the rule is “a capital at the start of each word”, an attacker knows it and applies the same rule: the number of possible phrases has not budged. It would be different if the capital fell at a randomly drawn position, but then the phrase would become impossible to remember. The digit, on the other hand, really is drawn at random, and the tool counts its 3.3 bits.
Can I have words in my own language?
Yes: two lists of 7,776 words are embedded, one French and one English, and the French page offers French first. Both are free of accented characters, so every word can be typed on any keyboard. The strength of the phrase does not depend on the language, only on the draw: what changes with the language is your ability to remember the phrase, and that is far from a detail.
Can I use this phrase with this site's encryption tool?
Yes, and that is exactly the intended use. The safe in the security corner derives its key from your password with six hundred thousand rounds of computation, which makes an attack very slow; combined with a six-word phrase, that is strong for a long time. It is also true for a PDF password, where it matters even more: that format does not slow password verification down, so the strength rests entirely on the phrase.
Can I build several and pick the one I like?
Yes, with no loss at all. Every draw is independent of the previous ones: choosing among three offered phrases does not reduce the entropy of the one you keep. What would reduce it is EDITING the phrase by hand so it sounds better, or systematically rejecting words you do not know. That does shrink the space of possibilities.
Six random words beat an eight-character password, and the tool PROVES it by the arithmetic. It also says what is useless: the capital and the separator are worth zero bits.
VerifyThe proof, step by stepThe network inspector check, explained one gesture at a time, with screenshots.
The cornerThe security cornerEncrypt a file, build a strong passphrase, check that a download has not been tampered with, strip the trackers from a link.