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ROT13 Encoder

Apply the ROT13 letter shift to text instantly.

Tool

Use this ROT13 encoder to transform text with the classic 13-letter rotation cipher. It is useful for puzzles, learning exercises, quick obfuscation, simple text experiments, and any task where you want to apply or reverse a ROT13 transformation without writing code.

About this tool

Use this ROT13 encoder to transform text with the classic 13-letter rotation cipher. It is useful for puzzles, learning exercises, quick obfuscation, simple text experiments, and any task where you want to apply or reverse a ROT13 transformation without writing code.

Use rot13 encoder when you need a fast browser-based result without extra setup. It works well for quick checks, one-off tasks, and routine formatting or calculation work.

Learn more

Why use this tool

How to use

  1. Paste the text into the input box.
  2. Run the tool to apply ROT13.
  3. Review the transformed output.
  4. Run it again on the result if you want to restore the original text.

Examples

Example

Input

Hello

Output

Uryyb

Applies the 13-letter rotation to each alphabet character.

Example

Input

Uryyb

Output

Hello

Running ROT13 again restores the original text.

Common errors

The user expects secure encryption.

Fix: Remember that ROT13 is only a simple text substitution and not secure protection.

Numbers and symbols are expected to change too.

Fix: ROT13 affects letters only, not punctuation or digits.

The output looks unchanged for non-letter-heavy input.

Fix: Check whether the input actually contains alphabet characters.

FAQ

What is ROT13?

ROT13 is a simple letter substitution that rotates alphabet characters by 13 positions.

Does ROT13 decode too?

Yes. Applying ROT13 twice returns the original text.

Is ROT13 encryption?

No. It is a simple substitution method, not secure encryption.

Is this ROT13 encoder free to use?

Yes. It works online in the browser.

When is ROT13 useful?

It is useful for puzzles, jokes, simple obfuscation, and learning exercises.

Use cases

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