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ROT cipher

Rotate letters by any amount from 1 to 25 with a slider — a variable ROT13.

Input
13
Output

ROT cipher

ROT13 shifts every letter by exactly 13 places, and ROT47 shifts every printable character by exactly 47 — both fixed by convention because that amount is its own inverse. This tool generalises the idea: drag the slider to any value from 1 to 25 and apply that rotation instead, a Caesar cipher you control rather than one number baked in.

In the default letter mode, only the 26 unaccented Latin letters A–Z and a–z rotate; case is preserved, and everything else — digits, punctuation, accented letters like č or ü, emoji and non-Latin scripts — passes through untouched. Turn on ROT47 mode to rotate every printable ASCII character from "!" to "~" within that 94-character band instead, using the same shift value. Spaces, line breaks and non-ASCII characters are still left alone.

One difference from ROT13 and ROT47 is worth knowing: because 13 is half of 26 (and 47 half of 94), running those twice restores the original — the same button encodes and decodes. A shift you choose yourself usually does not. To reverse it you need the complementary shift: 26 minus your shift in letter mode, or 94 minus it in ROT47 mode.

That suits puzzle hunts, escape rooms, geocaching hints and CTF challenges where the fixed shifts are too well known to hide anything. It is not real encryption — a shift cipher has just one number as its whole key space.

Everything runs locally in your browser. Nothing you type is uploaded, so it is safe to experiment with private text. Copy the result, download it as a .txt file, or send it back into the input to chain another transformation.

FAQ

How is this different from the ROT13 tool?
ROT13 always shifts by exactly 13. This tool lets you pick any shift from 1 to 25 with a slider, so you can generate any Caesar rotation, not just the classic one.
Why does applying the same shift twice not undo it?
ROT13 and ROT47 work as a single reversible button only because 13 and 47 are exactly half of their alphabets (26 and 94). Any other shift needs its complement — 26 minus the shift for letters, 94 minus it for ROT47 mode — to reverse it.
What does ROT47 mode change?
It switches the rotation from the 26 letters to all 94 printable ASCII characters ("!" through "~"), so digits and punctuation rotate too, using the same shift value from the slider.
Is my text uploaded anywhere?
No. The rotation runs entirely in your browser — your text never leaves your device.