I've recently gotten into cryptography and found a code which I just have not been able to decrypt. Any help? All I know is its in hexadecimal notation due to the 0x notation. Here it is: 0xB105F00D 0x6FA830D3

I think there's a time limit I have on how long to work out, but I'm not sure. I have tried using an alphanumeric cipher, Caesar shift etc. to no avail. Any ideas?

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    $\begingroup$ I'm pretty sure its not hexadecimal as that isn't a valid input $\endgroup$ – Beastly Gerbil Dec 1 '17 at 20:29
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    $\begingroup$ @BeastlyGerbil it is valid hexadecimal; B105F00D FA830D3 contains only 0-9 and A-F. There might be a digit missing from the second term, though. $\endgroup$ – Glorfindel Dec 1 '17 at 21:20
  • $\begingroup$ Yes, it is valid hexadecimal. Doesn’t mean you should try to interpret it as hexadecimal, though :-) $\endgroup$ – Bass Dec 1 '17 at 21:54
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    $\begingroup$ 0xB105F00D is (coincidentally perhaps) Hexspeak for "BIOS FOOD", I'm not sure about the second bit though. Try mixing out the numbers for letters they look like or sounds they're similar to (ST8, for example, could be State or S33 could be See). $\endgroup$ – Lio Elbammalf Dec 1 '17 at 22:48
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    $\begingroup$ If there is a time limit, this would be an ongoing competition? We can not help with those.. $\endgroup$ – Jason V Dec 2 '17 at 20:05

try xor.pw and copy 0xB105F00D into the first box and 0x6FA830D3 in the second box then press 'calculate XOR' and what appears in the 3rd box is your code You`ll get:


  • $\begingroup$ Welcome to puzzling! Have you tried the 'calculate xor' yourself? It'd be best to do that and edit that into your answer; otherwise, leave this as a comment. $\endgroup$ – Wen1now Dec 11 '17 at 9:21
  • $\begingroup$ yes i have tried this and i can confirm that it does work $\endgroup$ – ben b sings Sep 4 '18 at 13:28

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