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2026

Caesar Cipher

A rotating disc that teaches the Caesar cipher while you use it.

  • JavaScript
Privacidad
Todo en el navegador
Dependencias
Ninguna

My role

Sole developer

What it is

The Caesar cipher shifts every letter a fixed number of positions through the alphabet. It is the oldest known substitution cipher and protects nothing today, but it is the doorway to understanding what encryption means.

Why I built it

Because explaining an algorithm in words is far harder than letting someone drag the shift and watch the disc turn. The centrepiece isn't the text field — it's the disc, because that is where you see why one letter becomes another.

Decisions

No backend. There is no server that could read what you type: the algorithm is a handful of lines of JavaScript running in your own browser. For a tool that handles the user's text, having no server isn't a limitation — it's the feature.

No framework. HTML, CSS and JavaScript. Loading React to shift letters would multiply the page weight a hundredfold for nothing.