ROT13 & ROT47 Encoder
Encode and decode text with the ROT13 and ROT47 ciphers. ROT13 is its own inverse, so the same tool encrypts and decrypts. Free, private, instant.
Last reviewed by the Radiatus Cloud team
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Encode and decode with ROT13 and ROT47
ROT13 and ROT47 are simple rotation ciphers used to lightly obscure text, and this tool encodes and decodes both. ROT13 rotates letters by 13, and ROT47 rotates a wider range of characters, each being its own inverse.
How the ciphers work
ROT13 shifts each letter thirteen places, and because thirteen is half of twenty-six, applying it twice returns the original, so the same operation encodes and decodes. ROT47 extends the idea to a wider range of printable characters, rotating them by 47. Both are used not for security, they are trivially reversed, but to lightly hide text, a spoiler, a puzzle answer, so it is not readable at a glance but anyone can decode it. Understanding they provide no real protection is part of using them correctly.
Obscure, not secure
It runs entirely in your browser, so nothing you paste is uploaded and the result is yours to copy straight into a project, which lets you work on private code and data without anything leaving your machine.
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Frequently Asked Questions
What is ROT13?
A cipher that rotates each letter thirteen places. Since thirteen is half of twenty-six, applying it twice returns the original, so one operation both encodes and decodes.
What is ROT47?
An extension that rotates a wider range of printable characters by 47, covering more than just letters, but with the same self-inverse property.
Are these ciphers secure?
No. They are trivially reversed and provide no security. They are used to lightly hide text, like a spoiler or puzzle answer, not to protect it.
Why use ROT13 at all?
To obscure text so it is not readable at a glance, such as hiding a spoiler, while letting anyone who wants to decode it easily.
Is my text uploaded?
No. The encoding runs entirely in your browser.
Privacy & Security
All processing happens locally in your browser — nothing is uploaded.
How to Use
Type text and pick ROT13 or ROT47. Run it again on the output to decode.
Disclaimer: This tool is provided "as is" without warranty of any kind. Results are for educational and utility purposes.
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