Last time we’ve seen some popular fictional passwords, and how they are used in Exploit.in – a collection of 739,861,478 leaked passwords. I wanted to take another look at some popular numbers and how they are used in passwords.
π
How many digits of Pi have you memorized? I’ve got 6 digits after the decimal: 3.141592. Not bad, but could be better. Let’s see how far the Exploit.in community takes it:
17,713 password have exactly 7 decimal places of Pi (1415926). 1,626 have 10 decimal digits. The record is a single password with 37 digits of Pi – 1415926535 8979323846 2643383279 502884179. The last two digits in that password are cunningly reversed (79 instead of 97), so unfortunately they don’t count.
Here’s a breakdown for the digits of Pi in passwords:
Math constants
Same as with Pi, I’m only considering digits after the decimal point:
| Value | Digits | Passwords |
|---|---|---|
| e | 7182818284 | 337 |
| e | 71828182845904523536 | 7 |
| √2 | 4142135623 | 114 |
| √3 | 7320508075 | 21 |
| Phi | 6180339887 | 86 |
| Euler Mascheroni | 5772156649 | 1 |
Didn’t make it: Conway’s Constant, Khinchin’s constant, and Glaisher Kinkelin.
Fibonacci sequence
One advantage of the Fibonacci sequence is that if you forget your password you can always calculate it. 25,316 unforgettable passwords contain 8 Fibonacci numbers (1 through 21). Only 4 passwords make it all the way to the 15th number, 610:
Physics and Chemistry constants
| Number | Digits | Passwords | Light Speed | Meters/Second | 299792458 | 1988 | Light Speed | Miles/Second | 186282 | 298 | Light Speed | Kilometers/Second | 299792 | 2561 | Light Speed | Miles/Hour | 670616629 | 1 | Avogadro | 6.02×1023 | 6021023 | 259 | Avogadro | 6.022×1023 | 60221023 | 73 |
|---|
Avogadro passwords that make good use of special characters include m602x1023e and 602*1023.
Pop-culture numbers
Unsurprisingly, numbers that appear on TV or song lyrics make their appearance in passwords. I couldn’t find too many examples:
Music
| Tommy Tutone | 867-5309 / Jenny | 8675309 (Exact password) | 13894 |
| Tommy Tutone | 868-5309 / Jenny | 8675310 (contain) | 28231 |
| Queens of the Stone Age | Regular John | 16278263789 | 7 |
LOST
40,430 passwords are exactly 4815162342. Additional 34,318 password contain 4815162342, and another 1,058 passwords have The Numbers with separators, for example L48O1516S2342T.
See also
For a more serious analysis of password trends and common patterns:
- Analyzing the Patterns of Numbers in 10 Million Passwords – By Max Woolf
- How are users choosing their passwords on the internet?
- Why So Many People Make Their Password ‘Dragon’ – By Louise Matsakis, Wired (warning: soft paywall)
- Unmasked: What 10 million passwords reveal about the people who choose them
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