Image of a brain cheering

CryptoHack

A free, fun platform for learning modern cryptography

Image of a cloud pouring information into a head

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.

Level up image of a warrior

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?

New ideas in development

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
Do you have good eyes? (Breizh CTF) CTF Archive 0
RSATogether (ECSC 2024 (Italy)) CTF Archive 0
Authentification 1 (Breizh CTF) CTF Archive 0
One Round Crypto (ECSC 2024 (Italy)) CTF Archive 0
Greatest Common Multiple (CODEGATE CTF) CTF Archive 0
Weekly Top Users
#1 l1l_w31rd03 5535
#2 sujin 4160
#3 omelet 3730
#4 hthh 3150
#5 Romyna 2895
Recent Solves
Finding Flags minhtientntn
ASCII Dfmari
Modes of Operation Starter 0xGh4zy
Bytes and Big Integers YK_QK
Token Appreciation Ah_Error
Recent Solutions
Scalar Multiplication silentRoar 0
Point Addition silentRoar 0
Montgomery's Ladder silentRoar 0
Manyprime silentRoar 0
Extended GCD S4MTEL 0

Level Up

level up icon

You are now level Current level