ROT13 & Caesar Cipher Encoder/Decoder
Classic letter-substitution cipher — not real encryption.
A classical letter-substitution puzzle, not real encryption or security — don't use this to protect anything sensitive.
ROT13 is self-inverse — running it again on the output returns the original text.
What is this tool?
A Caesar cipher shifts each letter a fixed number of places through the alphabet, preserving case and leaving non-letters untouched. ROT13 (shift 13) is the classic special case — self-inverse, so applying it twice returns the original text. Other shifts need the complementary shift (26 - N) to decode, which this tool applies for you with one click. A classical obfuscation puzzle, not real encryption.
How to use it
- Type or paste text.
- Set the shift amount (defaults to 13 for ROT13).
- Use Decode to apply the complementary shift and reverse the transform.
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