How to use the ROT13 Encoder & Decoder
- Type or paste your text.
- The ROT13 version appears straight away.
- Paste ROT13 text to read it: running it again gives back the original.
- Click Copy.
What is ROT13?
ROT13 ("rotate by 13") replaces each letter with the one 13 places later in the alphabet: A↔N, B↔O, C↔P and so on. Because 13 is half of 26, doing it twice brings you back where you started. Hello becomes Uryyb, and Uryyb becomes Hello.
It's been used since the early days of Usenet to hide joke punchlines, spoilers and puzzle solutions, so readers see them only if they choose to. It offers no security at all. For other shifts, use the Caesar cipher tool.
Frequently asked questions
Is ROT13 encryption?
No. Anyone can reverse it instantly. It only stops people reading something by accident.
Does ROT13 change numbers?
No, only the letters A–Z. Digits, spaces and punctuation stay the same.
What is ROT13 of 'hello'?
'uryyb'.
Updated