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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 agentmon 16555
#2 Arvis 10315
#3 phebsv 4790
#4 aaanomy 3775
#5 RSeldon06 2775
Recent Solves
Hex sy791219927
Special Soundness mochaowo
From Private to Public Key LWE Ianneuh
Prime Power Isogenies osihlovec
Bytes and Big Integers AGO83
Recent Solutions
Modular Arithmetic 1 yuri981 0
ECB CBC WTF Anouar404 0
Passwords as Keys Anouar404 0
XOR Properties flapjack990 0
Modular Binomials flapjack990 0

Level Up

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