Shift letters by any amount, including the classic ROT13, instantly in your browser.
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Tell us what you think about Encode or decode ROT13 and Caesar cipher text.
- Runs entirely in your browser — your text is never sent to a server
- Shift by any amount, including the classic ROT13
- Free, no account required
How it works
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1
Paste the text, code, or token you want to encode or decode.
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2
Conversion happens instantly as you type.
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3
Review the result, including any decoded structure.
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4
Copy the result to your clipboard.
Why use this tool
Every dev utility, one place
Format, convert, encode, decode, and generate — no more juggling ten tabs.
100% private, always
Every tool runs in your browser — your code and data are never sent anywhere.
Works on any device
Runs on Windows, Mac, Linux, iOS, and Android — nothing to install.
Instant results
No queues, no build step — results update as you type.
Built to handle real data
Full Unicode support and RFC-compliant parsing, edge cases included.
Free, always
Free to use, with no rate limits, sign-up, or trial period.
Frequently asked questions
ROT13 is simply a Caesar cipher locked exactly at a shift of 13 characters.
No, only standard alphabetical characters are shifted; spaces and symbols are ignored completely.
Absolutely not; it is an ancient puzzle cipher that can be cracked in seconds by a computer or child.
Yes, uppercase letters map to uppercase equivalents, keeping the sentence structure intact.
Because there are only 25 possible shifts, you can easily guess it by brute-forcing the slider until English words appear.
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