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CryptoHack

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
ECLCG (HITCON CTF) CTF Archive 0
Sus (ImaginaryCTF) CTF Archive 0
Share (HITCON CTF) CTF Archive 0
Leet Universe (ImaginaryCTF (Daily)) CTF Archive 0
Hyper512 (HITCON CTF) CTF Archive 0
Weekly Top Users
#1 adwaadwa 3055
#2 l1nks 2360
#3 AlphaChaos 1720
#4 tacopeland 1680
#5 Al_ch 1575
Recent Solves
Bytes and Big Integers grupo3_jyep
Sharks on the Wire convyu
Secure Protocols convyu
Greatest Common Divisor Baradika
Finding Flags Namatullah09
Recent Solutions
Gotta Go Fast fssl 0
Bruce Schneier's Password fssl 0
JSON in JSON fssl 0
RSA or HMAC? fssl 0
No Leaks fssl 0

Level Up

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