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Passwords · Patterns
I remember the pattern but not the numbers: how that is used
«I know what it was like but not what it was» is the sentence that most often precedes a successful recovery. A pattern is not a vague memory: it is a precise description of a small set of possibilities.
What a pattern is, in practice
A pattern is the shape of your password without the specific data. For example: «a word with an initial capital, followed by four digits, followed by an exclamation mark». That, which seems to say nothing, defines a perfectly bounded set.
| Pattern you remember | Possibilities |
|---|---|
| Word + 4 digits (unknown word) | many millions |
| One of 10 words of yours + 4 digits | 100,000 |
| One of 10 words + a year between 1970 and 2015 | 450 |
| One of 10 words + a year, with or without a capital | 900 |
| The above, with or without one of three final symbols | 2,700 |
Two thousand seven hundred possibilities are minutes of work even on the slowest wallet there is. And notice what caused the jump between the first and second rows: supplying a list of your words. Only you can do that.
The patterns I see again and again
- A proper name with an initial capital plus a four-digit year.
- A word plus the day and month of a birthday.
- Two words run together, no spaces, the second capitalised.
- A word with letters replaced by similar-looking digits.
- A password you used elsewhere with something tacked on the end to «make it different».
The last one is especially valuable. If you remember what your «usual» password was back then, even if this one was different, this one was probably that one with something added. That turns the problem into testing a few dozen suffixes.
How to describe your pattern so it is useful
- Write the structure, not the password: «word, number, symbol».
- Say roughly how many characters it had.
- Make a list of candidate words, even if there are twenty.
- Make a list of the numbers you used: years, birthdays, house numbers, plate numbers.
- Say which symbols you tended to use and where you put them.
Write that on paper, not on your phone or in the cloud. And when it is no longer needed, destroy it: that list describes how you build all your passwords, not just this one.