Encrypt and decrypt text using the Caesar cipher substitution method.
Input
Encoded Text
Uryyb Jbeyq
About this calculator
Overview
The Caesar cipher is a simple encryption technique where each letter is shifted by a fixed number of positions in the alphabet. Named after Julius Caesar, who used it for military communications. Easy to break but historically significant.
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Pro Tips
Shift of 13 (ROT13) is self-inverse—apply twice to get original.
Caesar cipher is vulnerable to frequency analysis attacks.
Preserve case (uppercase/lowercase) for readability.
Numbers and symbols typically remain unchanged.
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Fun Facts
"Julius Caesar used a shift of 3 for military messages."
"Caesar cipher is a special case of substitution cipher."
"Frequency analysis was developed by Al-Kindi in 9th century."
"ROT13 is commonly used in online forums to hide spoilers."
Formula: Encrypted Letter = (Original Letter + Shift) mod 26
