Image via http://www.flickr.com/photos/redspotted/272104/

The perils of using a poor-quality password for an email account, online bank account or shopping service are well-known, but what about the PINs used for cashpoints and smartphones?

A researcher in the US set out to find the least commonly used four-digit PIN based on the 3.4 million that have been leaked by security breaches over the years.

Every single one of the 10,000 possible combinations of four digits (0000, 0001, 0002 up to 9999) was found in the data, which allowed some interesting analysis to be performed.

The result was a top-20 table of most popular PINs and, perhaps unsurprisingly, the most popular sequence turned out to be “1234” — it made up nearly 11% of the 3.4 million PINs used.

In other words, anyone trying their luck with a found or stolen cashpoint card stands a one in ten chance of getting it to work in cash machine by entering “1234”.

Next most popular PINs are the almost as obvious “1111” (6%), followed by and “0000” (2%).

In total, the top 20 most popular pins accounted for over 25% of the 3.4 million PINs used for the research.

Most Popular PINs

Position
PIN
% Frequency
#1
1234
10.71%
#2
1111
6.02%
#3
0000
1.88%
#4
1212
1.20%
#5
7777
0.75%
#6
1004
0.62%
#7
2000
0.61%
#8
4444
0.53%
#9
2222
0.52%
#10
6969
0.51%
#11
9999
0.45%
#12
3333
0.42%
#13
5555
0.40%
#14
6666
0.39%
#15
1122
0.37%
#16
1313
0.30%
#17
8888
0.30%
#18
4321
0.29%
#19
2001
0.29%
#20
1010
0.29%

Other interesting findings to come out of the research were that people seemed to prefer even numbers over odd and that the seemingly random “2580” was surprisingly popular, in 22nd place.

Surprising, that is, until you realise that these are the four digits than run down the middle of a mobile phone keypad.

The researcher also compiled a top 20 list of the least popular PINs, with “8068” coming in last (10,000th) place.

If you’re thinking about changing your four-digit PINs in the light of this information though, it’s probably best not to now that everyone else knows about it…

Least Popular PINs

Position
PIN
% Frequency
#9980
8557
0.001191%
#9981
9047
0.001161%
#9982
8438
0.001161%
#9983
439
0.001161%
#9984
9539
0.001161%
#9985
8196
0.001131%
#9986
7063
0.001131%
#9987
6093
0.001131%
#9988
6827
0.001101%
#9989
7394
0.001101%
#9990
859
0.001072%
#9991
8957
0.001042%
#9992
9480
0.001042%
#9993
6793
0.001012%
#9994
8398
0.000982%
#9995
738
0.000982%
#9996
7637
0.000953%
#9997
6835
0.000953%
#9998
9629
0.000953%
#9999
8093
0.000893%
#10000
8068
0.000744%