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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 melnicek 5500
#2 jackoha 3185
#3 khanhtai 2720
#4 F25 2310
#5 fjukh7872 2080
Recent Solves
Hex tmm29
ASCII adi_2936
RSA Decryption niaream
Mister Saplins The Prover fjukh7872
Great Snakes Kron14
Recent Solutions
Passwords as Keys cbr4l0k 0
Computing Public Values wapoy64924 0
Quadratic Residues a1372321 0
Favourite byte a1372321 0
Favourite byte m0ckinjay 0

Level Up

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