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A fun, free 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 jebil123 2820
#2 leyremonreal 2395
#3 whale120 2130
#4 lalba 2050
#5 ot 1740
Recent Solves
Diffusion through Permutation gobirds
Hex natsuha
ASCII zephyria
Curves and Logs vanupier
Great Snakes zephyria
Recent Solutions
Broken RSA zenobia 1
Diffie-Hellman Starter 3 3b0_0d 0
Diffie-Hellman Starter 2 3b0_0d 0
Salty 3b0_0d 0
Modulus Inutilis 3b0_0d 0

Level Up

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