Classic Ciphers

Apply ROT13 and Atbash both ways.

Runs locallyNo signupMobile readyCopyableFree

⚿Classic Ciphers

All processing happens locally

Input text

Algorithm

Caesar shift (1-25)

Result

Classic Ciphers is a classic cipher helper for puzzles, processing runs locally in your browser, so your input never reaches a server.

Results update as you change values; copy or download when ready.

Paste or type your content into the input field at the top, or press the sample button to load demo data.
Adjust the options below the input, such as output format, separators, letter case or precision.
Press the main button to run the conversion. Results appear instantly in the output panel without a page reload.
When the result looks right, use the copy button in the corner, or download it as a local file.

Clean up stray spaces and line breaks before pasting for more accurate results.

Is ROT13 secure?+

Not at all; it is a fixed shift and trivially reversed. It hides spoilers, not secrets.

How does Atbash work?+

It maps the alphabet in reverse: A to Z, B to Y, leaving digits untouched.

Is Classic Ciphers free to use?+

Yes. The tool is completely free with no usage limits, and you never need an account or a sign-in.

Is the text I enter uploaded anywhere?+

No. All processing runs locally in your browser, so the input never reaches a server and is never logged or stored.

Does Classic Ciphers work on a phone or tablet?+

Yes. The layout is mobile-first, so inputs and buttons stay comfortable on phones and tablets in both orientations.

Can I copy the result into my own document?+

Yes. A copy button in the output panel puts the result on your clipboard, and you can also download it as a text file.