From Caesar's simple substitution to RSA and elliptic-curve key exchange. Interactive visualisations that demystify the mathematics keeping modern communication secure.
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Ciphers, key exchange, hashing, and public-key cryptography — visualised
Cryptography simulations make the mathematics of secure communication tangible and interactive. Caesar and Vigenère cipher visualisers show classical substitution and polyalphabetic encryption letter by letter, making frequency analysis attacks obvious. RSA key-generation animations walk through Euler's totient function, modular exponentiation, and the relationship between key length and factoring difficulty.
Diffie–Hellman key-exchange simulations animate the public/private colour-mixing analogy and then show the actual modular-arithmetic protocol, demonstrating how two parties can agree on a shared secret over an insecure channel. Hash-function collision visualisers demonstrate the avalanche effect: how a one-bit change in input flips roughly half the output bits. These visualisations serve introductory cybersecurity courses and system designers learning where cryptographic primitives should be applied.
Each simulation in this category is built with accuracy and interactivity in mind. The underlying mathematical models are the same ones used in academic research and professional engineering — just made accessible through a web browser. Changing parameters in real time and observing the results is one of the most effective ways to build intuition for complex scientific and engineering concepts.
Topics and algorithms you'll explore in this category
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