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CryptoHack

A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 chopingu 2690
#2 billbob 2030
#3 Minh_Fan_Boy 1605
#4 GarrusW 1580
#5 askiii 1555
Recent Solves
Diffusion through Permutation soulking
Lemur XOR y44444n1ss
XOR Starter Gxsus
Bytes and Big Integers mcmoodoo
Modular Arithmetic 2 rio166
Recent Solutions
Stream of Consciousness Rust 0
Bean Counter Rust 0
Signing Server nk0 0
Ron was Wrong, Whit is Right nk0 0
Infinite Descent nk0 0

Level Up

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