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About Rot13 Encoder Online
This tool applies the ROT13 cipher to text. ROT13 shifts every Latin letter forward by 13 positions in the alphabet, so A becomes N, B becomes O, and so on. Applying ROT13 a second time gives back the original text (because the alphabet has 26 letters).
ROT13 is not secure encryption. It was widely used in Usenet posts to hide spoilers, punchlines to jokes, or potentially offensive content from accidental reading. The reader knows ROT13 is in use and can decode at will, but won't read the text by accident while scrolling.
Use it for puzzles, casual content hiding, or recreating the feel of late-1990s message-board culture.
How to use this tool
How to apply ROT13 substitution to text
Paste the text
Drop the plaintext into the "Text" field. ROT13 shifts each A–Z letter by 13 positions (`A↔N`, `B↔O`, …, `M↔Z`). Case is preserved; digits, punctuation, spaces, and non-Latin characters are left untouched.
Press Run
Result returns a single `encoded` field. Examples: `Hello, World!` → `Uryyb, Jbeyq!`; `5 PM` → `5 CZ`. Apply ROT13 twice and you get the original back — encoder and decoder are identical operations.
What it isn't
ROT13 is a curiosity, NOT encryption. It hides text from a casual reader (joke punchlines, mild spoilers) but anyone can reverse it in seconds. Don't use it for passwords, secrets, or anything that needs to stay confidential.
When to use it
Forum spoiler tags, puzzle hints, Easter eggs, USENET tradition. If you want to obfuscate code constants from grep, ROT13 buys you about 3 seconds — pick anything else.