Image of a brain cheering


A fun, free 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
1n_jection CTF Archive 0
FaILProof CTF Archive 0
Real Mersenne CTF Archive 0
C0ll1d3r CTF Archive 0
FaILProof Revenge CTF Archive 0
Weekly Top Users
#1 Alpagalcyaquois 1790
#2 artart78 1700
#3 01142076 1440
#4 shd33 1410
#5 dawnas 1295
Recent Solves
SSH Keys sevenkplus
Chinese Remainder Theorem samerwazan
Salty Hazuma
Bytes and Big Integers baynoni
RSA Starter 5 missbc
Recent Solutions
Modular Binomials zeroc 0
Adrien's Signs zeroc 0
ECB Oracle cryptick_geo 0
No Way Back Home 1s0m0rph1sm 0
Crossed Wires HIGH0101 0

Level Up

level up icon

You are now level Current level