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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 deborahajewole 3015
#2 leezy 2100
#3 piretopire 1980
#4 DrUmar 1710
#5 NghiTranMuggle 1565
Recent Solves
Finding Flags tomvar
XOR Starter ayepino
Exceptional Curves Skinbow
Salty Pligonstein
Modular Arithmetic 2 trigpolynom
Recent Solutions
Legendre Symbol pcman 0
Quadratic Residues pcman 0
Modular Inverting pcman 0
Modular Arithmetic 2 pcman 0
Modular Arithmetic 1 pcman 0

Level Up

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