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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 TanookiWannabe 2340
#2 Garab 2135
#3 lucasrodriguez 1810
#4 tanmaymunjal64 1760
#5 jiji 1425
Recent Solves
Favourite byte mooncake
Base64 solomind
XOR Properties mooncake
Gotta Go Fast Migsej
Hex solomind
Recent Solutions
Modular Inverting g4B 0
Modular Arithmetic 2 g4B 0
Modular Arithmetic 1 g4B 0
RSA or HMAC? vanluongkma 0
Vote for Pedro epistemologist 0

Level Up

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