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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 bimbambap 16555
#2 hellooooowww 15305
#3 burdock 12545
#4 DexterJie 10545
#5 AltafSaleh 6065
Recent Solves
Hex boboyaga
ASCII boboyaga
Extended GCD Yosaf_Ahmed
RSA Signatures lll111
Great Snakes Youthh
Recent Solutions
Favourite byte Kran 0
Legendre Symbol rito_sand 0
Greatest Common Divisor TeraP 0
You either know, XOR you don't TeraP 0
XOR Properties TeraP 0

Level Up

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