ROT13 Encoder / Decoder

Apply the classic ROT13 cipher — each letter is shifted 13 places, so encoding and decoding are the same operation. The original spoiler-hider of early internet forums.

100% free No uploads Runs in your browser No signup

ROT13 (apply to encode or decode)

Input text

0 characters

Result

—

ROT13 shifts every letter exactly 13 positions — because the alphabet has 26 letters, applying it twice returns the original text. That means the same button encodes and decodes.

How to use the ROT13 Encoder / Decoder

1
Open the tool above — it is already running, no install or account needed.
2
Enter your input and adjust the options to match what you need.
3
Copy or download the result — everything was processed locally in your browser.

Private by design

This tool runs 100% inside your own browser using local JavaScript — your input never touches a server. That makes it instant, offline-capable in many cases, and private even for sensitive data.

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