Welcome to Codebreaker!

Codebreaker is the official platform for Singapore Informatics Olympiad training and contests. We have run selection for the International Olympiad in Informatics for the delegations of Singapore and Indonesia, as well as countless official national and school training programmes.

2274 problems

All problems

924000 submissions

Recent submissions

9269 users

Rankings

Public Contests
Traffic (CloudFlare)

Submissions Per Day
Most Attempted Problems (Past Week)
Problem Users
japan2026 201
evilbz 200
addition 185
cpicsort 178
urarareader 174

Most Submitted Problems (Past Week)
Problem Submissions
evilbz 938
cpicgame 761
exam 688
addition 637
urarareader 620