Arena generates fresh, validated coding problems styled like the platforms you'll actually face — LeetCode, HackerRank, CoderPad — then coaches you in real time without ever spoiling the answer.
Static problem banks go stale and tell you the answer. Arena generates an endless, validated stream and meets you where you are.
Every problem is AI-generated and then proven solvable — a reference solution must pass 100% of its own tests before you ever see it. No broken or unsolvable questions.
The engine tracks where you struggle, ask for hints, or stall — and serves the next problem to consolidate or stretch you. Smart next, not a dumb queue.
Stuck? Graded help nudges you toward the idea — kind, then hint, then reveal — so you build the muscle instead of memorizing a solution.
A real coding environment, a live coach, and a stream that never runs out.
Choose a topic or a company cram. Arena builds a personalized stream and a course tuned to that target.
Write and run Python against real tests. Ask the coach anything in plain English — it drives the app and grades your runs.
Clean solve? It steps you up. Struggled? It reinforces. Your progress and workspace follow your account on any device.
Styled exactly like LeetCode, HackerRank, or a CoderPad pairing round — so practice feels like the real thing.
Generate a personalized cram for a specific company or topic — a themed, visual course built around the concepts that matter.
"Give me a harder graph problem." The AI coach understands your workspace and runs the app with you, in sync.
Sign in and every learner gets an isolated workspace, budget, and history — your code is never mixed with anyone else's.
Free to try — no card needed. You start with a batch of credits (more when you sign in); when it runs out, a cram pack unlocks a full prep run. No subscription, no expiry, no surprise bills.
Our biggest bundle — 15,000 credits at the best price per credit. Enough for this search and the next one; buy once, prep whenever the interviews come.
Practice is free to use right now — drop your email and we'll tell you the moment cram packs go live.
Already have a code? Redeem it →
Yes — you start with a batch of free credits to try it (a few more when you sign in), no card needed. It's a one-time taste, not a daily refill; when it runs out, a prepaid cram pack unlocks a full prep run.
No. Coaching is deliberately graded — it nudges you toward the idea, then a hint, and only reveals as a last resort, so you actually learn the pattern.
Every problem is validated before you see it: a reference solution must pass 100% of its own generated tests in a real sandbox, or it's thrown out.
Sign in and your workspace, history, and remaining budget follow your account on any device.
Securely through Lemon Squeezy, our merchant of record — they handle billing and tax. We never see your card details.
Start practicing in seconds — your first problems are one click away.