Wiki / Reverse Engineering UCards

This is some basic technical information about the University of Sheffield’s UCards. It’s not that interesting…

Front Barcode

The barcode on the front of the card is a barcode encoding the UCard Number. The standard symbology for a barcode is Code 128, but UCards use the less dense (and therefore longer) Code 39. It’s likely that this is intentional so the barcode is easier to scan.

Back Magnetic Stripe

The magnetic strip just contains the UCard number on the second track. The first is empty, and the third is either empty or not present at all - it’s not possible to tell with my low-budget magstripe reader.

When read with a standard magnetic stripe reader this produces ;_Ucard Number_? (“;” and “?” are the start and end sentinels for the 2nd track.)


The card doesn’t have an RFID chip (or anything else hidden internally).