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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 sontran999123 3565
#2 Harachili 3080
#3 redsti 2610
#4 viflaem2 2190
#5 medb 2030
Recent Solves
Base64 0xAp0stl3
Too Many Errors radare
LWE Intro 1Eb
LWE Background 1Eb
What's a Lattice? 1Eb
Recent Solutions
XOR Properties Gvriel 0
SSH Keys Papascruff 0
Privacy-Enhanced Mail? Papascruff 0
Quadratic Residues Papascruff 0
Greatest Common Divisor Und3aD_gh0sT 0

Level Up

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