ROT13 Encode / Decode — Text ↔ ROT13 Cipher

ROT13 is a simple letter substitution cipher that shifts A↔N, B↔O, etc. It is often used for spoilers, light obfuscation, and forum/email text. This tool encodes plain text to ROT13 and decodes ROT13 back to text (the operation is symmetric). Runs 100% locally in your browser — no uploads — and works offline after installing ToolMill as a PWA.

Encoding

Try it

Examples

Encode plain text with ROT13

Input

Attack at dawn!

Output

Nggnpx ng qnja!

Decode ROT13 text back to plain text

Input

Guvf vf n EBG13 grfg.

Output

This is a ROT13 test.

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