Eligibility
Anyone who has not completed secondary school may compete officially. Dual-enrolled secondary students remain eligible.
Competition
Twenty problems. Ninety minutes. One clear challenge.
The 2026 Open is an individual, short-answer competition designed to begin with approachable ideas and end with problems that demand genuine invention.
20problems
90minutes
48hour starting window
$0entry fee
At a glance
Everything you need to know.
Official division
All eligible pre-university participants compete in the overall official ranking.
Junior ranking
Students in grade 10 and below, or equivalent, also appear in a separate junior ranking.
Unofficial participation
Undergraduates and adults may take the same test unofficially without official awards.
Format
20 short-answer problems completed individually in 90 minutes.
Scoring
One point per problem, with no penalty for an incorrect answer.
Contest window
Start any time from November 14 at 00:00 UTC through November 15 at 23:59 UTC.
Allowed tools
Pen and paper only for official attempts; no calculators, code, online search, or outside help.
Language
The official competition language is English.
Topics
A broad view of discrete mathematics.
- 01Counting
- 02Probability
- 03Graph Theory
- 04Pigeonhole Principle
- 05Extremal Arguments
- 06Games
- 07Invariants
- 08Recursion
Awards
Performance, recognized clearly.
Gold, Silver, and Bronze designations; junior and country recognition; and digital certificates.
Integrity
Care at every stage.
Original writing, independent answer verification, blind test-solving, and faculty review support the final paper.
Appeals
A defined review window.
Participants may appeal scoring within 72 hours after preliminary results are published.