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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
What a Curve! (Breizh CTF) CTF Archive 0
GLP420 (HackTM CTF) CTF Archive 0
unrandom DSA (HackTM CTF) CTF Archive 0
kaitenzushi (HackTM CTF) CTF Archive 0
d-phi-enc (HackTM CTF) CTF Archive 0
Weekly Top Users
#1 Mikbrosim 3005
#2 Phaazhzhasse 2320
#3 jsack 1825
#4 Nissen 1705
#5 Katu2ou 1615
Recent Solves
Great Snakes pandawoop
Chinese Remainder Theorem Gravitar
Ron was Wrong, Whit is Right itko
Finding Flags pandawoop
Base64 c1nd3r3114
Recent Solutions
ECB Oracle skriptr 0
Beatboxer wang606 0
Extended GCD thebug 0
Greatest Common Divisor thebug 0
Jack's Birthday Hash cruzzer 0

Level Up

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