The blog

If I recall it cor­rect­ly it was when I gave a lec­ture at a Rotary-meet­ing a few years ago, that a man came up to me and excit­ed­ly said, ​“I have to tell you a smart trick I use so that I do not have to remem­ber the PIN-code for my cred­it card for petrol.”.

This real­ly caught my atten­tion, as I am famil­iar with this need to remem­ber PIN-codes myself. Although I only have a hand­ful of cards I use reg­u­lar­ly, there are some PINs I am often a tad ner­vous when enter­ing into the PIN pad.

I have occa­sion­al­ly for­got­ten both the code for my petrol cred­it card as well as my phone, and it always results in a lot of time-con­sum­ing fix­ing which I would prefer­ably avoid. My bank- and deb­it card codes are not a prob­lem, but my petrol-com­pa­ny will for instance not let me choose my own PIN when renew­ing the card, which then forces me to remem­ber a new code with every new card.

Write the code on the card (!)
Back to the Rotary meet­ing. The man eager to share the tip prob­a­bly want­ed to shock me when he blurt­ed out ​“I write the code on the card.”

When he saw my skep­ti­cal­ly raised eye­brows, he continued:
​“Well, this how it’s done. I have cho­sen a phrase that con­tains ten let­ters, such as ​‘read things’. The ten let­ters rep­re­sent the ten dig­its from 0 to 9. The PIN I receive I then trans­late into the cor­re­spond­ing let­ters. I can then with­out con­cern or wor­ries write the four-dig­it let­ter-com­bi­na­tion that remains on the card, since you need the code-phrase to deci­pher the code.”

I think this is very clever. (Per­son­al­ly though, I would write the cipher in a note on my cell phone instead of direct­ly on the card.)

Do this
If you want your PIN-codes writ­ten down so you do not have to remem­ber them and still be able to feel con­fi­dent that they will not fall into the wrong hands, then do this:

1. Find a phrase with ten char­ac­ters that will con­sti­tute your key-phrase. If you have trou­ble decid­ing what the best phrase to use could be, think of a few and let chance help you choose one by pulling one of the sug­ges­tions writ­ten on pieces of paper out of your closed palm.


2. Choose one of your PIN-codes and trans­late it into let­ters using the key-phrase.


3. Write the PIN-let­ter code on a small piece of paper which you keep in your wal­let or in a note on your cell phone so that you can eas­i­ly access the code when­ev­er you for­get it.

One alter­na­tive to this trick is using an encrypt­ed pass­word ser­vice such as 1Password or Last­Pass.

Sim­ply eas­i­er card-management
If you in this way or in some oth­er way, keep track of what PIN-codes you have got, you will not have any trou­bles with order­ing new codes, cut your card in pieces and make a cash with­draw­al when it is def­i­nite­ly an incon­ve­nience doing so. You eas­i­ly avoid one of the every­day-life sit­u­a­tions which is unnec­es­sar­i­ly time-con­sum­ing and will have more time for what you real­ly need to con­cen­trate on.

How do you remember?
How do you remem­ber your PIN-codes? Leave a com­ment and share your tip.