ROT13 Encode & Decode
Shift letters by 13 — encode and decode with the same operation. This tool does both encode and decode on one page — just pick a mode, paste your text, and click. Everything runs on your device, nothing is sent to a server.
Everything runs in your browser. Your data is never sent to our servers.
Example
Example Input
Hello
Example Output
Uryyb
How to Use
- 1Choose Encode or Decode mode at the top.
- 2Type or paste your text into the Input field.
- 3Click the button (or press Ctrl+Enter) to process. The result appears in the Output field.
- 4Click Copy to copy the result, or "Swap input/output" to quickly reverse the operation.
About ROT13
ROT13 ("rotate by 13") shifts each letter 13 positions in the alphabet. Because the alphabet has 26 letters, applying ROT13 twice returns the original text — so encode and decode are identical.
How it works: A↔N, B↔O, and so on; digits and symbols are left untouched. ROT13 is not real encryption — it only hides text from casual reading.
ROT13 is classically used on forums and Usenet to hide spoilers or puzzle answers so they aren't read accidentally. It is not for security.
FAQ
Can this ROT13 tool both encode and decode?
Yes. This is a single page with a toggle — use Encode mode to transform text, and Decode mode to reverse it. No need for two separate pages.
Is my data sent to a server?
No. ROT13 is processed entirely in your browser. The text you enter never leaves your device.