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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 N0tPresl3y 4805
#2 francois 3850
#3 AAlessandro 3245
#4 Aryaethn 2290
#5 PhoenixKLua 2170
Recent Solves
Great Snakes Lawton
Great Snakes Ling
Great Snakes Caiyro
Great Snakes EpifAlex
Great Snakes usertestaccount0
Recent Solutions
Modular Square Root geo_gkez 0
Quadratic Residues geo_gkez 0
Legendre Symbol geo_gkez 0
You either know, XOR you don't m0x90 0
Confusion through Substitution Veen0o21 0

Level Up

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