ROT and Atbash
ROT transformations shift letters, digits or printable ASCII characters. Atbash reverses the alphabet: A becomes Z, B becomes Y, and so on.
Multi-tool decoder
Test several simple decodings on the same message.
Codes
Paste a coded or suspicious message, then quickly test several transformations: ROT, Caesar, Atbash, reversals and A1Z26 numeric variants.
Message to test
Paste a message, then run the tests.
Settings
Results
Add a message to run the tests.
Dedicated tools
Quick explanation
This decoder helps you explore several paths without switching tools for every attempt. It applies the most useful transformations for simple puzzles and lets you copy each result or reuse it as a new source.
Try this too
Not sure which path to choose?
Use the code detector first to spot the most likely formats, then come back here to test several transformations.
Additional information
Understand the multi-tool decoder
The multi-tool decoder applies several common transformations to the same message. It is useful when you have a clue, but want to compare several results quickly without opening each tool separately.
It complements the code detector: the detector helps spot plausible paths, while the multi-tool decoder lets you test them directly.
Caesar shifts
The Caesar table displays the 25 possible shifts. It is convenient for visually spotting a readable result, then copying it or reusing it as a new source.
Reversals
Reverse readings test the full text, words one by one and lines. These attempts are simple, but often useful in short messages or puzzles.
Numeric codes
When the message contains numbers, the tool can suggest A1Z26, A26Z1, A0Z25 and A25Z0 variants. These transformations are only displayed if the values remain compatible with the alphabet.
For more precise work on these variants, use the A1Z26 tool. To analyze an unknown message before testing it, use the code detector.
Copy or reuse
Each result can be copied or placed back into the source field. This makes it easy to chain several attempts, for example a shift followed by a reversal.
Cautious results
The decoder does not decide which transformation is correct. It displays readable attempts that are quick to compare, without hiding other possibilities.
Privacy
The transformations run directly in your browser. The text you enter is not sent to the server to generate the results.
Limits and reuse
AppErgo tools are provided free of charge for practical and informational purposes. Although care is taken in their design, a result may be incomplete, unexpected or incorrect. Before relying on a result for any important use, check it using an appropriate method.
To report a bug in the tool, you can use the dedicated bug report form.
Results produced by AppErgo tools may be copied and reused freely. When publicly reusing a result, a method or an AppErgo page, a link to the relevant page is appreciated.
Unless otherwise stated, AppErgo texts, images, visual elements, scripts, templates and internal components remain the property of AppErgo.
For any other request, you can contact the webmaster.