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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 jotaghz 3530
#2 DeuxMonade 3095
#3 IVLeagueHacker 2650
#4 ratatata 1830
#5 d4pr0 1790
Recent Solves
Extended GCD Fireblock
Quadratic Residues M4DD0C74
Greatest Common Divisor Fireblock
Lemur XOR Fireblock
CERTainly not nb0mb
Recent Solutions
Greatest Common Divisor sacsrfice 0
Noise Cheap xtea418 0
Confusion through Substitution LashaG 0
Round Keys LashaG 0
ECB CBC WTF TanR 0

Level Up

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