Card number workbench

A card number is mostly not a secret. The first six digits are a public lookup table, the last one is arithmetic, and the checksum throws away nine of every ten guesses for free. Cover part of a number, tell it which bank the logo said, and watch what is actually left to guess.

Nothing is uploaded. The BIN table and the maths are both in this page. Use the test numbers; there is no reason to type a real one.

1 Type the digits that are readable, hide the rest.

Spaces and dashes are ignored. Hide a digit with a bullet, an x, a ? or an *.

Test numbers
Cover up
2 Whose card is it? The logo on the card is enough. Search the public BIN list.