Two prime numbers meet in the silence of mathematical space. One multiplies by the other, giving birth to a modulus. Euler's totient function calculates the count of coprime numbers, and then a pair of keys is found — public and private. A message is raised to a power modulo, transforming into ciphertext. The inverse operation returns the original number.
This is not textbook theory. This is an interactive RSA visualization where every step of the algorithm is broken down into formulas you can touch with your hands. Where you can change the primes and see how the modulus changes. Where you can enter a message and watch it transform into encrypted and back.
The mathematics of cryptography here is not hidden behind abstractions. It's shown explicitly — from choosing prime numbers to computing the modular inverse. Every formula is rendered through KaTeX, every step is accompanied by an explanation in three languages.
A project for yourself. To understand how what protects your data on the internet works. To see the mathematics behind encryption. To connect neurons in your head and realize why factoring large numbers is a hard problem, and why this makes RSA secure.