How can we help you?How can we help, assist, and support you?

Click 'Start Free' on the homepage, fill out the registration form with your email and password, and verify your email address to get started.

AlgoArena supports 17 languages, including JavaScript, Python, Java, C++, C#, Go, Rust, and TypeScript. You can select your preferred language in the code editor during battles.

Your ranked Elo increases when you win live human ranked battles and decreases when you lose them. The amount of change depends on the skill difference between you and your opponent.

Our matchmaking system pairs you with opponents of similar skill levels based on ranked Elo, ensuring fair and competitive battles.

If you disconnect, you have 2 minutes to reconnect. If you don't return, the battle is forfeited and your opponent wins.

Yes! Visit the Practice section to solve problems at your own pace without affecting ranked Elo.

Free includes unlimited ranked battles, the full practice library, and community features, plus 1 AI Analysis of your solutions a day, 5 Rena hints a day while you practice, and a one-time AI credit for the builder. Full Rena chat and mock interviews are on the paid plans.

In Settings, open Subscription and pick Pro or Ultimate. Pro adds Rena chat, mock interviews, and a monthly AI credit allowance. Ultimate removes the monthly caps on Rena chat conversations and mock interviews. Rena chat still uses your monthly AI credits.

Yes, you can cancel your subscription at any time from your account settings. You'll retain Pro features until the end of your billing period.

Try refreshing the page or clearing your browser cache. If the issue persists, switch to a different browser or contact support.

Check your spam folder and ensure notifications are enabled in your account settings. Add contact@algoarena.net to your contacts.

The first player to pass all tests wins the battle. If the timer runs out, the stronger partial result (more tests passed) takes it. Review the detailed feedback in your battle history.