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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
RSA or HMAC? Part 2 Crypto on the Web 100
Roll your Own Mathematics 90
Dancing Queen Symmetric Ciphers 120
SSH Keys General 35
LFSR Destroyer Misc 250
Weekly Top Users
#1 sam15341534 2945
#2 iskim517 2725
#3 fsh 2515
#4 zeski 2465
#5 crawfish 2320
Recent Solves
Salty coc0a
Keyed Permutations fiftypie
Collider fsh
Hash Stuffing fsh
RSA or HMAC? Part 2 fsh
Recent Solutions
Confusion through Substitution CCC 0
Round Keys CCC 0
ECB Oracle Toi2908 0
SSH Keys Bugtrack 0
Real Eisenstein mathno1 0

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