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Transforms & generators

ROT13 encoder/decoder

A 13-place Caesar shift. Run it twice and you are back where you started.

Processed in your browser — nothing is uploaded

Converted

Converted

A–M swap with N–Z. Punctuation and digits stay.
Last reviewed 2026-09-10.
FAQ
Questions, answered
Do I need a decode mode?
No. ROT13 is involutive — the same function decodes.
Is it secure?
No. It is a joke cipher and a Usenet classic.
Does my text leave the browser?
No. The ROT13 tool runs in JavaScript on this page. Your paste is not uploaded.
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