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by y4mi 1420 days ago
Aren't card PINs only 4 numbers long? That's almost 10k possible combinations I believe, pretty trivial to put together.

Checking which corresponds to what card is the hard step because you need access to an acquirer to my knowledge, and you'll lose that access quiet quickly if you attempt too many incorrect combinations.

2 comments

You can use more than 4 digits if you want a more secure PIN.

EMV (the card standard used by all modern chip/contactless cards) supports PINs between 4-12 digits in length.

I have been wanting to try a 4< digit pin, but I expect payment terminals to go bonkers because they don’t accept it. Have any of you a card pin longer than 4?
Six-digit pin works well for me in European countries - Czechia, Germany, Austria, Spain, Italy.
My girlfriend used a 5-digit PIN for over 10 years in the UK and never had any issues that I can recall.

I’d change mine too except I use the PIN so infrequently (99% contactless now days) I’m worried I’d forget the new one!

Just try and be surprised - no issues.
just don't try to use it in some remote exotic place, 4 places are often hardcoded but you may still be able to withdraw/pay, or not
Mine is eight digits, never tried it outside Canada yet.
All pins in my country are 5 digits. Which can be annoying for four-d visitors (depends on the bank, and I've not heard of problems for a while).
Damned, with 5 digits, the cost of storage alone is a deterant for a rainbow table