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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 Jinx 3815
#2 Angmar_ 3780
#3 nous 3155
#4 fjukh7872 2600
#5 heeheeheehar 2220
Recent Solves
Adrien's Signs tolliob
You either know, XOR you don't shahipeasant
You either know, XOR you don't GameCity
Symmetry mrk756
Hamiltonicity 2 (CryptoHack) minipif
Recent Solutions
Quadratic Residues B0tm4n 0
The Matrix mpg 0
Square Eyes red909 0
Round Keys Sparrow09 0
Structure of AES Sparrow09 0

Level Up

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