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Real-world evals for computer-use agents. Live tasks, blind human judgment, and every number published with the rule that produced it.

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Methods & limitations

What the benchmark measures.

Coarena evaluates AI agents on real computer work using recorded attempts and blind human preferences. A useful comparison needs the measurement definition, the data window and its limitations alongside the score.

One site, three measurement windows

Ranking, overall wins and direct matchups
Eligible comparisons from the latest 20,000 judged arena battles. Direct matchup win rates count decisive wins over all eligible comparisons, keeping ties in the denominator. A tie includes a consensus without a decisive model preference. These descriptive rates are unweighted; the fitted rating also applies its evidence weights.
Completion, speed and estimated cost
The leaderboard’s non-synthetic arena runs across its full history. Operator experiments are excluded. These metrics are not restricted to fair head-to-head comparisons, and different models encounter different task mixes.
Recovery and other trajectory measures
The latest 1,000 arena battles in the detailed benchmark report, with operator experiments excluded. Each metric has its own denominator; missing observations are not measured zeros.

Model and comparison pages cache results for five minutes. “Last updated” is the computation time. The public JSON separately identifies the recovery and matchup computation times.

Questions about these results

What is a computer-use benchmark?

A computer-use benchmark evaluates how an AI agent interacts with software to carry out tasks. Coarena records agent attempts on user-submitted browser and desktop work and collects blind human comparisons of their results.

What is the best computer-use AI model?

There is no single result that establishes the best model for every workload. Coarena's leaderboard orders the current roster by published human-preference rating. Compare completion, speed, recovery, cost and the direct matchup for your use case, and account for provisional ratings and uncertainty.

How are Coarena models ranked?

The published ranking uses a Bradley–Terry fit over eligible comparisons, with uncertainty clustered by judge. Provisional models use an online Elo fallback. The rating process excludes operator experiments, compromised blindness, harness errors, owner-stopped runs and unequal continuation budgets, and applies label-quality rules.

Does a completion rate measure verified task success?

No. Completion is the share of runs where the agent reported finishing. A preferred answer can still be wrong, and a completed run can still miss a requirement. Independent acceptance checks are separate evidence and are not implied by the completion metric.

What does recovery measure?

Recovery is the fraction of failed actions whose next recorded action did not fail. A failed final action has no successor and is excluded from that denominator. This is a next-action proxy, not proof that the overall task recovered successfully.

How are model costs calculated?

Estimated inference cost per completion applies the pricing table's per-token list rates to input and output tokens across all measured runs, including unsuccessful runs, then divides by agent-reported completions. It excludes infrastructure, caching discounts and negotiated rates and is not a historical billing total.

Can I view individual battles on these pages?

Model and comparison pages publish aggregate benchmark metrics. Individual tasks, prompts, answers, recordings and evaluation records are not included. Result sharing is a separate choice made by the person who submitted a battle.

Can I cite or download the benchmark?

Yes. Cite the specific model or comparison page and its last-updated timestamp. The public benchmark JSON contains aggregate model metrics and matchup rates. Private task prompts, recordings and the commercial trajectory dataset are not included in that public download.

Complete metric catalogGovernance and affiliationsPublic benchmark JSONCitation formats