ROT13 Encoder and Decoder
Encode or decode text with ROT13 in your browser. One click works both ways, keeps case, and leaves numbers and punctuation unchanged.
Independently verified for accuracy
Calculator by Toolsloft ↗Apply ROT13 to any text to lightly scramble it or to read a message that was already scrambled. ROT13 is its own reverse, so one button covers both directions. It is commonly used to hide spoilers, puzzle answers, and punchlines without truly encrypting them.
How this is calculated
ROT13 rotates each letter 13 places through the 26-letter alphabet, the standard definition used across Usenet and countless text tools. Since 13 is exactly half of 26, running the text through twice restores the original. Case is preserved and characters that are not letters are left unchanged.
How to use
- Type or paste your text into the input box.
- The ROT13 result appears instantly in the output box.
- Paste ROT13 text back in to decode it, since the operation is its own reverse.
Examples
- Encode:
Hello → Uryyb - Decode:
Uryyb → Hello
FAQ
- Do I need a separate decode button?
- No. ROT13 shifts letters by 13 places, and doing that twice brings you back to the start, so the same operation both encodes and decodes. Paste scrambled text in and you get the original out.
- Is ROT13 secure?
- No, and it is not meant to be. It hides text from a casual glance, which is why it is used for spoilers and puzzle answers, but anyone can reverse it instantly. Do not use it to protect anything sensitive.
- What happens to numbers and symbols?
- They are left exactly as they are. ROT13 only rotates the letters A to Z, and it keeps upper and lower case intact.