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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
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 vanluongkma 5830
#2 naylor0 2080
#3 CayCon 1540
#4 Just_Riccio 1300
#5 PriyaPathak 1300
Recent Solves
Greatest Common Divisor Sooon
You either know, XOR you don't cybernole
Size and Basis nabizzle
Transparency UNLaM_Crip_Grup2
Great Snakes levinhhung20032
Recent Solutions
Trust Games klmn 0
RSA vs RNG klmn 0
Nothing Up My Sleeve klmn 0
Chinese Remainder Theorem Nosiume 0
Quadratic Residues Nosiume 0

Level Up

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