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Free Online ROT13 Cipher Converter

Rotate letters by 13 spaces to obfuscate or decode text strings.

How to use & benefits of ROT13 Cipher

Obfuscate and Decipher ROT13 Code

ROT13 ("rotate by 13 places") is a simple substitution cipher that replaces a letter with the 13th letter after it in the Latin alphabet. Because there are 26 letters in the alphabet, ROT13 is symmetric: applying it twice returns the original text.

Our free online ROT13 cipher rotates text inputs instantly:

  • Bi-Directional Action: The same button deciphers code blocks and hides text messages.
  • Preserves Numbers: Numbers, symbols, spaces, and punctuation remain unaltered.
  • Instant Conversions: Text encodes dynamically as you type.

Key Benefits & Features

✓
Symmetric Cipher

The same rotation encodes plaintext and decodes ROT13 strings.

✓
Clean Filtering

Leaves digits, punctuation symbols, and spaces unaltered.

✓
Offline Operations

Encoding is processed locally, ensuring texts stay secure.

How to Use the ROT13 Cipher Step-by-Step

This utility runs entirely inside your browser using client-side JavaScript. We prioritize your security: none of your inputted text is logged or stored.

  1. 1

    Paste your standard text or ROT13 message into the input field.

  2. 2

    Review the decoded or encoded text output instantly.

Practical Examples

Input Example

hello world

Expected Output
uryyb jbeyq

Frequently Asked Questions (FAQ)

What is ROT13?▼

ROT13 is a simple Caesar cipher offset that rotates characters in the alphabet by 13 steps.

Is ROT13 secure?▼

No, ROT13 is not cryptographically secure. It is primarily used in online forums to hide spoilers, punchlines, or puzzle answers.

Does ROT13 handle capital letters?▼

Yes, it shifts uppercase characters to uppercase and lowercase characters to lowercase.

Explore category: Security & Cryptography
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