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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
wise sage (CTFZone) CTF Archive 0
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
Weekly Top Users
#1 VZXeFMTUq4o 2755
#2 klmn 2495
#3 gilcu3 2465
#4 HackersLove 1860
#5 Nezaa 1590
Recent Solves
Backpack Cryptography klmn
Modular Inverting duongloc0510
Diffie-Hellman Starter 1 Dope_cat
Modular Arithmetic 2 duongloc0510
Legendre Symbol Mangara
Recent Solutions
XOR Properties rust_chan 0
Marin's Secrets VZXeFMTUq4o 0
Infinite Descent VZXeFMTUq4o 0
Crossed Wires VZXeFMTUq4o 0
Everything is Big VZXeFMTUq4o 0

Level Up

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