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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
Hamiltonicity 2 (CryptoHack) CTF Archive 0
Fischlin's Transformation (CryptoHack) CTF Archive 0
OR Proof (CryptoHack) CTF Archive 0
Ticket Maestro (CryptoHack) CTF Archive 0
Additional problems (CSC Belgium) CTF Archive 0
Weekly Top Users
#1 0xndavd 5170
#2 Blackash2023 4775
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#5 v3r7ux 3965
Recent Solves
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You either know, XOR you don't what1slove77
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Recent Solutions
Let's Prove It Again maple3142 1
Let's Prove It maple3142 0
Honest Verifier Zero Knowledge 0xndavd 0
Special Soundness 0xndavd 0
Oracular Spectacular ConnorM 0

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