ROT13 Encoder & Decoder
Encode or decode text using ROT13 — a 13-position Caesar cipher that's self-inverse.
What is ROT13 Encoder & Decoder?
ROT13 is the most famous letter-substitution cipher: shift each letter 13 positions. Because 13 is exactly half of the 26-letter alphabet, applying ROT13 twice returns the original text. It's used in Usenet posts to hide spoilers and punchlines from casual scanning — not for any actual security.
Frequently asked questions
Is ROT13 secure?▼
No. It's a puzzle/obfuscation, not encryption. Anyone can decode it instantly.
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