Unknown encoded string

Question

Do you have any tip on how to decode this string (encode my string to this format)? Seems to be something like base64 combined with...

n69k0J0xLSEqh0IFG2ZGgeZwLZ0SuiSe:sO6uELP0yW:S17zihfs6qpW20E7R7U2NTZsXzW1YKYIoEUqBXGvygY5CkKolsoh

I hope original string maybe sth like this:

ttInd=0&i=750&s1=1234&s2=4321

It is definitely not base64. Where is this data coming from exactly? That might give a clue as to what type of encoding(s) are supported by that format/protocol. — Remy Lebeau, Jan 24 '14 at 17:44
I'm sorry but I can't say **today**. I can only present another strings like these: `dCqkxyICL8vSuMr8H5ORzQ--` => `key=8680001&ttInd=5297` `3NYuZuHJIRoqCAQ0LDD:2Q--` => `key=2830001&ttInd=2755` `ziqhDiw5xVEVivOwpfR.RQ--` => `key=4620001&ttInd=2871` — Anette D., Jan 24 '14 at 18:06
Without any context, how do you expect people to answer? There are many different data-to-text encoding algorithms. — Remy Lebeau, Jan 24 '14 at 19:18
There are base64 variants for URLs and identifiers, but the values you show do not match those algorithms. So whatever the site is using, it is likely either a custom algorithm, or a rare variant of an existing algorithm. Have you thought about maybe contacting the site admin and ask? — Remy Lebeau, Jan 24 '14 at 20:11

score 0 · Answer 1 · answered Jan 24 '14 at 19:33

If we assume that -- represents padding, and the fact that the encoded data can have : and . characters in it, one might first jump to the conclusion that it could be a modified base64 variant. But the length of the encoded data is <= the length of the input data (depending on whether & really is & or is actually & before encoding), so it can't be based on base64, which always produces encoded data that is longer than the input data. So there is either a simple replacement algorithm in play, or some amount of bit compression is being used. Either way, without more context about what kind of format/protocol this encoded data is actually being used in, there is simply no way to answer this question as-is. There are simply too many data-to-text encoding algorithms used in the real world to narrow this down by trial-an-error.

Unknown encoded string

1 Answers1