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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
1337crypt CTF Archive 0
Substitution Cipher III CTF Archive 0
1337crypt v2 CTF Archive 0
Signature CTF Archive 0
pekobot CTF Archive 0
Weekly Top Users
#1 GalHorowitz 4540
#2 drdoctor 4010
#3 itamar_rot 2510
#4 Nics 1520
#5 YonPog 1375
Recent Solves
Hex Psofos
Manyprime rain_thursday
ASCII Psofos
Modular Inverting PurFikshun
Great Snakes Psofos
Recent Solutions
Prime and Prejudice remy_o 1
RSA Backdoor Viability remy_o 1
Adrien's Signs shynt04 0
No Way Back Home joachim 0
Favourite byte badxcode 0

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