Caesar Cipher Encoder & Decoder
Encode or decode text with a Caesar cipher — letter substitution by a fixed shift amount.
What is Caesar Cipher Encoder & Decoder?
The Caesar cipher is one of the oldest known encryption methods, dating back to Julius Caesar's military correspondence around 50 BC. Each letter is shifted by a fixed number of positions in the alphabet. With only 25 possible keys, it's trivially broken — but it's a great teaching tool for understanding cryptography fundamentals.
Frequently asked questions
What's a shift of 13?▼
That's ROT13 — a self-inverse special case where applying it twice returns the original text.
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