About this site
I'm James Marchant. I work in cards, mostly on scheme implementation and compliance projects.
This started as a bookmarks problem. Every project reaches a point where you need to know what a particular TVR bit actually means, or which data element carries the POS entry mode, or whether a currency has two minor units or three. I knew most of it. I did not trust my memory enough to act on it, so I would search, and end up on whichever site came up first.
That is fine when you are looking up a code. It is a different matter when the thing you want to check is a card number, or a chip trace pulled off a live terminal. Plenty of sites will decode those for you, and nearly all of them ask you to paste the data into a box and press a button. What happens to it after that is anyone's guess. I was never comfortable with it, and I don't think anyone working in this industry should be.
So these are the tools I reach for most often, built the way I wanted them. Everything runs in your browser and there is no server for your data to reach. That is not a promise about how carefully I handle things, it is a property of how the site is put together, and the privacy page shows you how to confirm it instead of asking you to take my word for it.
I'm still learning this space and I expect to keep changing things as I go. Some of these tables will have gaps. Specifications get revised and schemes update their acceptance rules, so something that is correct today can quietly stop being correct. If you find a mistake, or there is a lookup you keep needing that isn't here yet, I'd genuinely like to hear about it.