For security students, CTF players and puzzle solvers learning how substitution ciphers work. You get the shifted or mirrored text instantly, with case and punctuation kept.
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You enter
ROT13 on "Attack at dawn"
The tool shows
Nggnpx ng qnja
There are only 25 possible shifts, so try each one until readable text appears. To undo a known shift of 3, apply a shift of 23.
ROT13 shifts by 13, half of the 26-letter alphabet, so a second pass moves each letter back to where it started. The same setting encodes and decodes.
No. They are trivially broken and only hide text from casual reading. Use them for learning and puzzles, and real encryption such as AES for anything sensitive.
Yes. It is free, needs no sign-up and runs entirely in your browser, so what you type is not uploaded. You only sign in if you want to email a result to yourself or save it to your CareerByteCode profile.
