Solve real olympiad problems one at a time. Pick a past paper by year, practise a single topic, or race a friend in a duel.
Pick a subject above. Its topics and questions will show up here.
Race another student on the same problem. The first correct answer wins and both ratings update.
Pick a subject. We choose the problem, then wait for someone to join.
Problems you bookmarked. Tap one to solve it.
While solving, tap the bookmark icon to keep a problem here for later.
You left the duel tab. Tab switching is not allowed during a duel — it is considered cheating and will be recorded.
Accepting defeat forfeits this duel and awards victory (+ ELO) to your opponent.