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.

2270 problems

All problems

916000 submissions

Recent submissions

9260 users

Rankings

Public Contests
Traffic (CloudFlare)

Submissions Per Day
Most Attempted Problems (Past Week)
Problem Users
japan2026 202
evilbz 201
addition 182
urarareader 170
exam 169

Most Submitted Problems (Past Week)
Problem Submissions
evilbz 938
cpicgame 751
exam 681
addition 624
urarareader 612