ROT13 Encoder
Apply the classic ROT13 letter substitution to text (encode and decode are the same).
ROT13 shifts every letter 13 places in the alphabet, a simple substitution long used to hide spoilers and punchlines in plain sight. Because 13 is half of 26, applying it twice returns the original — so the same tool encodes and decodes.
How to use rot13 encoder
- 1. Paste your text.
- 2. Each letter is shifted 13 places.
- 3. Copy the result (run it again to reverse).
When to use ROT13 Encoder
Hide a spoiler
Obscure a spoiler or answer so it's only readable if someone deliberately decodes it.
Lightweight obfuscation
Scramble text just enough that it isn't readable at a glance.
Learn substitution ciphers
See how a classic rotation cipher works.
What changes and what doesn't
Only the 26 English letters are rotated, and capitals stay capitals: "Hello" becomes "Uryyb". Digits, punctuation, spaces and accented letters such as ș or é are left untouched. ROT13 became the standard way to hide spoilers and punchlines on Usenet newsgroups, because anyone could undo it but nobody would read it by accident.
Frequently asked questions
How do I decode ROT13?
Run the text through ROT13 again — applying it twice returns the original, so encode and decode are the same operation.
Is ROT13 secure?
Not at all — it offers no security, only casual obscurity. Anyone can reverse it instantly.
Is my text private?
Yes — it's processed in your browser.