How to make a passphrase you can remember

Several random words beat a short scramble of symbols on both counts: harder to guess, and possible to keep in your head.

A passphrase is several words chosen at random and joined together. The appeal is that human memory is good at words and bad at punctuation, so you can carry a strong passphrase around in your head — which matters for the handful of secrets a password manager cannot store, starting with the password to the password manager.

Step-by-step

1. Choose how many words. Four is a reasonable floor; five or six for anything protecting other secrets.
2. Pick a separator. Hyphens, spaces or nothing. This does not meaningfully change the strength.
3. Generate, and read the entropy. The figure is derived from this list's actual size.
4. Learn it before you rely on it. Type it a few times. If a phrase will not stick, generate another; there is no shortage.

The strength is in the choosing, not the words

The critical requirement is that the words are chosen independently and at random. A phrase you pick is not random — people reach for related words, song lyrics, and things on their desk, all of which an attacker can enumerate far faster than the raw word count suggests.

This generator uses a 559-word list, which makes each word worth about 9.13 bits. Four words is roughly 36.5 bits; six words about 54.8. Those numbers are computed from the list actually in use, not copied from a Diceware article about a 7,776-word list — a distinction most passphrase tools blur, always in their own favour.

Capitalisation and a stray digit

Adding a capital letter and a number, in a position you choose, adds very little: an attacker who knows the pattern gains almost nothing to search. If a site insists, add them at the end and do not imagine you have bought much. Adding a whole extra word buys far more than any amount of decoration.

Frequently asked questions

How many words is enough?

Four words is around 36.5 bits with this list, which is fine for an ordinary account behind rate limiting. For a master password or disk encryption, use six or more, where guessing offline stops being realistic.

Is it weaker because the word list is public?

No. The strength assumes the attacker knows the list — it comes from which words were chosen, not from the list being secret. Any system whose security depends on hiding its design is a bad one.

Can I swap a word I don't like?

Generate a new phrase instead. Rejecting words you dislike is a preference, and preferences narrow the pool in ways that are hard to quantify.