I'm looking for a tool to reverse engineer a checksum character. Just something to brute force through most commonly used checksum char algorithms without the needing to implement every single one of them from scratch. The numbers I'm dealing with look like this:


(I will get some more samples)

And the data breakdown (929441812022112009904) is as follows:

  • 92944: vendor machine id
  • 18: year
  • 12: month
  • 02: day
  • 21120: uid, incremental for each operation
  • 0990: price (as in 09.90$, so capped at 99.99$)
  • 4: checksum character

The last two numbers threw me off a bit since they differ by 1 on the uid number and have the same check digit.

So for all of the above numbers we get:


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