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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
Do you have good eyes? (Breizh CTF) CTF Archive 0
RSATogether (ECSC 2024 (Italy)) CTF Archive 0
Authentification 1 (Breizh CTF) CTF Archive 0
One Round Crypto (ECSC 2024 (Italy)) CTF Archive 0
Greatest Common Multiple (CODEGATE CTF) CTF Archive 0
Weekly Top Users
#1 NetKingJ 13070
#2 MuhaiminHasanein 11625
#3 Abstergo 6835
#4 Waeel79 6170
#5 HackX1 6070
Recent Solves
Encoding Challenge Tainted_Fool
Finding Flags Doozle
Finding Flags BrianOjeda
Bytes and Big Integers angelg12
Round Keys nasser20
Recent Solutions
Lemur XOR 4rg0 0
Passwords as Keys 4rg0 0
Bringing It All Together 4rg0 0
Round Keys 4rg0 0
Diffusion through Permutation 4rg0 0

Level Up

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