Compete in coding tournaments

Enter 1v1 coding battles and ICPC-style team contests run by colleges and clubs, with the CodeKairo account you already have, in any of 13 languages. Every accepted solve counts on your profile, streak and roadmap.

How do I take part in a tournament on CodeKairo Battles?

Sign in with your CodeKairo account — or create one on Battles, free; it works on codekairo.com too. For a knockout, open the tournament and register before registration closes (the organizer may ask for an email on their domain, an invite code or their approval), then check in during the hour before the start. For an ICPC-style contest the organizer enters your team, so signing in with the email or username they listed is all you do. You solve in the same editor as on CodeKairo, in any of its 13 languages, against hidden tests. Every accepted solve is an ordinary CodeKairo submission: it counts toward your solved problems, heatmap, streak and roadmap, and your profile lists every tournament with where you finished.

How it works

  1. Find your tournament. The tournaments page lists what is open for registration and what is live, from verified colleges, clubs and companies. Your organizer may also send you the link.
  2. Register, or be entered. Register yourself for a knockout; for a contest the organizer enters your team. Your own registrations and their status sit at the top of the tournaments page.
  3. Turn up and solve. Check in for a knockout in the hour before the start. The match or contest room is the CodeKairo editor you know, with the problem, the clock and — in a knockout — your opponent's progress.
  4. Keep what you earned. Solves count on your CodeKairo profile, the problem carries a solved-in-a-tournament mark, and your placement sits in your profile's Tournaments section.

Who it is for

Students competing for their college, club members on a contest night and developers entered by their company — anyone who would like a tournament result to sit on the same profile as the rest of their practice.

Frequently asked questions

Do I need a separate account for Battles?
No. Battles uses your CodeKairo account: sign in on Battles with email, Google or GitHub, or arrive already signed in from codekairo.com. An account created on Battles works on CodeKairo too, and both are free.
How do I enter a knockout?
Open the tournament and register before registration closes. Depending on the organizer you may need an email address on their domain, an invite code or their approval. Then check in during the hour before the start — only players who checked in are seeded.
How do I join an ICPC-style contest?
You do not register yourself: the organizer enters every team and names each member by CodeKairo email or username. Sign in with that account and the contest is listed under your tournaments.
Which languages can I use?
All 13 the CodeKairo judge accepts: JavaScript, TypeScript, Python, Java, C++, C, C#, Go, Kotlin, Swift, Rust, PHP, Ruby.
Do tournament solves count on my CodeKairo profile?
Yes. An accepted submission in a tournament is an ordinary CodeKairo submission: it counts toward your solved problems, activity heatmap, streak and roadmap stages, and pays XP the first time you solve that problem. The problem is marked as solved in a tournament, and your profile lists every tournament you played with where you finished.