Shift letters with ROT13 or any Caesar cipher offset.
Loading ROT / Caesar…
How to use ROT / Caesar
Open the ROT / Caesar tool.
Paste or type your text, code or a token into the input field.
The output updates as you type. Adjust the options if you need a different format.
Copy the result, or share the URL to hand the exact input to someone else.
About ROT / Caesar
Apply a ROT/Caesar shift cipher to text. Slide the shift from 0–25 (ROT13 is the classic self-inverse), use quick presets, or invert the current shift. Only A–Z letters rotate; digits, spaces and punctuation pass through unchanged.
What people use it for
Encode or decode ROT13 text (common for spoiler hiding).
Apply or reverse a Caesar shift for a puzzle or lesson.
Frequently asked questions
Is ROT13 reversible?
Yes. ROT13 is its own inverse, so applying it twice returns the original text.
Is this secure?
No. A Caesar cipher is trivially broken and is for fun or obfuscation only, never real protection.
Is it private?
Every calculation happens on this page, in your own browser. Your input is never sent to a server and never logged, which also means the tool keeps working when you are offline.