What the tool does, how to run it, and what to expect from the result.
A Caesar cipher replaces each letter with the one a fixed number of places further along the alphabet: with a shift of 3, A becomes D and "hello" becomes "khoor". Julius Caesar reportedly used a shift of 3. With only 25 possible keys it is trivial to break, and this tool does it for you: in decode mode it tries every shift and ranks the results by how closely their letter frequencies match English.
Short, plain-language definitions for the formats and settings above.
A quick way to understand who this helps, what it solves, and where it connects next.
Anyone who needs this done quickly, privately and free.
Using the caesar cipher without installing anything or signing up.
Short answers for the questions people usually have before trying a utility like this.
Paste the message with Decode selected. The tool tries all 25 shifts and lists the most English-looking results first; click one to apply it. Longer messages rank more reliably.
Yes, it is the Caesar cipher with a shift of 13. Because the alphabet has 26 letters, applying it twice returns the original text.
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Encode or decode as you type. Case, spaces and punctuation are kept.