Free Online Tool
ROT13 Converter
Apply the ROT13 letter-substitution cipher to your text.
The ROT13 Converter lets you apply the ROT13 letter-substitution cipher to your text. Paste your text below and the converted result appears immediately — no waiting, no upload, and nothing saved anywhere.
How to use the ROT13 Converter
- Paste your original text into the input box.
- Choose any conversion options offered above.
- Copy the converted result, or download it as a .txt file.
- Use Clear to start over with new text.
Key features
- Converts instantly as you type, with no delay.
- 100% private — your text stays in your browser.
- Free to use, with no sign-up and no daily limit.
- Handles both short snippets and long documents well.
Questions
Frequently asked questions
Is the ROT13 Converter free to use?
Yes — the ROT13 Converter is completely free, with no sign-up, no trial period, and no hidden limits.
Is my text uploaded anywhere when I use the ROT13 Converter?
No. The ROT13 Converter runs entirely in your browser using JavaScript. Your text is processed on your own device and is never sent to a server.
Can I use the ROT13 Converter on my phone?
Yes. The ROT13 Converter works in any modern browser, including on mobile devices, with no app to install.
Is there a limit to how much text I can use?
There's no artificial limit. Because everything runs in your browser rather than on a server, the ROT13 Converter can generally handle as much text as your device can comfortably process.
Keep going
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