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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
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 billbob 2155
#2 GarrusW 1580
#3 Minh_Fan_Boy 1370
#4 Rust 1345
#5 cuonghoccrypto51 1335
Recent Solves
Great Snakes Gabry154
Legendre Symbol Carlos_Castaneda
Finding Flags Gabry154
Legendre Symbol NGSM
Confusion through Substitution Kuerbiskern
Recent Solutions
Infinite Descent nk0 0
Greatest Common Divisor pcman 0
You either know, XOR you don't pcman 0
Favourite byte pcman 0
XOR Properties pcman 0

Level Up

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