Scramble and unscramble text with the self-inverse ROT13 and ROT47 rotation ciphers — perfect for hiding spoilers and puzzle answers, all in your browser.
Updated
Both ciphers are self-inverse — run the output through again to reverse it.
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Quick start
Pick a cipher, paste your text, copy the result — nothing leaves your browser.
Choose ROT13 (letters only) or ROT47 (all printable ASCII). Both are self-inverse.
Type or paste into the input pane; the scrambled output updates live.
Hit Copy or ⌘/Ctrl+Enter. To decode, apply the same cipher again.
In-depth guide
ROT13 and ROT47 are letter-rotation ciphers — a special case of the Caesar cipher with a fixed offset. They scramble text into something unreadable at a glance but recoverable by anyone, which makes them perfect for hiding spoilers and puzzle answers, and useless for real security. This tool applies both in your browser; because each is its own inverse, the same action encodes and decodes.
ROT13 shifts each ASCII letter 13 positions along the 26-letter alphabet, wrapping around at the end (A→N, N→A). Digits, spaces, and punctuation are left alone. Because 13 is exactly half of 26, encoding and decoding are the same step.
ROT47 works on the 94 printable ASCII characters (codes 33–126) and shifts by 47 — half of 94 — so it also rotates digits and symbols. Spaces and control characters are untouched.
These ciphers are for casual concealment, not confidentiality:
If you need actual secrecy, use a real cipher — try an AES encryption tool with a key instead.
ROT13 and ROT47 are obfuscation, not encryption. Never use them to protect passwords, tokens, or any sensitive data.
The rotation happens character-by-character in your browser. No text is uploaded, logged, or stored, so even though ROT is not secret-keeping, the tool itself never sees your data on a server. Everything is discarded when you close the tab.
No. ROT13 and ROT47 are simple character rotations applied in your browser. Nothing is transmitted — open DevTools → Network and you will see no requests while you type.
Run the scrambled text through the same cipher again. Both ROT13 and ROT47 are self-inverse: applying the rotation twice returns to the original, so there is no separate decode mode — just paste the encoded text and read the output.
ROT13 rotates only the 26 ASCII letters by 13 places, leaving digits, punctuation, and spacing untouched. ROT47 rotates all 94 printable ASCII characters (codes 33–126) by 47 places, so it also scrambles numbers and symbols, producing more thoroughly obfuscated output.
No. ROT13 and ROT47 are classical obfuscation, not encryption. They use a fixed, public rotation with no key, so anyone can reverse them instantly. Use them to hide spoilers, puzzle answers, or mildly offensive jokes from casual view — never to protect real secrets.
Historically ROT13 hid spoilers and punchlines: the text is unreadable at a glance but trivially decoded by anyone who chooses to. The rotation by 13 is convenient because the Latin alphabet has 26 letters, so encoding and decoding are the same operation.
ROT13 transforms only A–Z and a–z; ROT47 transforms only printable ASCII. Any character outside those ranges — accented letters, CJK, emoji — passes through unchanged, so non-ASCII text is preserved exactly.
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