Caesar Cipher Encoder
Encode and decode text with a Caesar shift cipher.
About the Caesar Cipher Encoder
The Caesar Cipher tool shifts each letter of your text by a fixed amount to encode it, and shifts back to decode. Set the shift to 13 and you get the classic ROT13. Letters wrap around the alphabet while numbers, spaces and punctuation stay untouched. It is a fun introduction to cryptography and works entirely in your browser.
How to use it
- Type your message and set a shift value (13 for ROT13).
- Click 'Encode' to scramble or 'Decode' to unscramble.
- Copy the result.
Frequently asked questions
Is this secure encryption?
No. A Caesar cipher is easily broken and is meant for learning and fun, not for protecting sensitive information.
What is ROT13?
ROT13 is a Caesar cipher with a shift of 13. Because the alphabet has 26 letters, applying ROT13 twice returns the original text.
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