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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 SasukeDough 2600
#2 pantelis 2220
#3 lydxn 2095
#4 Manas9323 1830
#5 nadhirzoghlami 1800
Recent Solves
Favourite byte syntthetix
XOR Properties syntthetix
Bytes and Big Integers Teeth
Quadratic Residues SnowF0X
Favourite byte duru
Recent Solutions
Jack's Birthday Hash AlanSmithee 0
Crossed Wires AlanSmithee 0
Adrien's Signs fitrafep 0
Quadratic Residues fitrafep 0
Ron was Wrong, Whit is Right yazeedallabadi24 0

Level Up

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