Developer ToolsEncoders & DecodersFree Tool
Caesar Cipher
Shift letters through the alphabet by a custom amount you choose, generalizing ROT13 to any shift value.
How to Use Caesar Cipher
- 1Enter your text
- 2On a new line, enter the shift amount (default 3 if omitted)
- 3Click Process
- 4Copy the shifted output
Frequently Asked Questions
Enter your text, then on a new line, the shift number — e.g. 'Hello' then a line with '3' shifts each letter 3 positions (Hello → Khoor). If no shift is given, it defaults to 3.
Use the negative of the original shift (or 26 minus the shift) — e.g. text shifted by 5 decodes with a shift of -5 or 21.
No — with only 25 possible shift values, it can be broken instantly by trying all of them (or by frequency analysis). It has no real cryptographic security, same as ROT13 (which is just the Caesar cipher with a fixed shift of 13).
No — only letters A-Z/a-z are shifted; numbers, punctuation, and spaces pass through unchanged.
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