RE-Bench
Seven open-ended ML research-engineering environments with human-expert baselines. Score normalized to reference solutions.
In the authors’ words
Frontier AI safety policies highlight automation of AI research and development (R&D) by AI agents as an important capability to anticipate. However, there exist few evaluations for AI R&D capabilities, and none that are highly realistic and have a direct comparison to human performance. We introduce RE-Bench (Research Engineering Benchmark, v1), which consists of 7 challenging, open-ended ML research engineering environments and data from 71 8-hour attempts by 61 distinct human experts. We confirm that our experts make progress in the environments given 8 hours, with 82% of expert attempts achieving a non-zero score and 24% matching or exceeding our strong reference solutions. We compare humans to several public frontier models through best-of-k with varying time budgets and agent designs, and find that the best AI agents achieve a score 4x higher than human experts when both are given a total time budget of 2 hours per environment. However, humans currently display better returns to increasing time budgets, narrowly exceeding the top AI agent scores given an 8-hour budget, and achieving 2x the score of the top AI agent when both are given 32 total hours (across different attempts). Qualitatively, we find that modern AI agents possess significant expertise in many ML topics – e.g. an agent wrote a faster custom Triton kernel than any of our human experts' – and can generate and test solutions over ten times faster than humans, at much lower cost. We open-source the evaluation environments, human expert data, analysis code and agent trajectories to facilitate future research.
- Level
- Research frontier Researchers, on open problems or tasks that take days
- Scored
- Checked automatically A program checks the result against an answer key, unit tests or the expected final state.
- Answers
- Agent task Many steps in a terminal, browser, desktop, app, game or robot.
No scores here yet
No lab, leaderboard or Epoch AI run has reported a score for RE-Bench yet.
Labs report it only in system cards
We read the headline results of 479 launch posts from 51 labs, and none of them list this benchmark. Some system cards do, below.
6 system cards report it, from 2 labs
Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.
| Date | Document | Score | As the document writes it | Section |
|---|---|---|---|---|
| 19 Feb 2026 | | 1.27 | RE-Bench (Deep Think mode): human-normalised average score 1.27. Optimise LLM Foundry runtime 47 s vs human reference 94 s (FSF results table, p.9) | AI R&D risk |
| 18 Nov 2025 | | RE-Bench subset of 5 tasks, normalised scores, 32-hour budget, chart without printed values (Figure 4) | AI R&D risk | |
| 7 Jul 2025 | | RE-Bench, 5 of 7 tasks, 32-hour budget: best agent solutions achieve between 50% and 125% of best expert-written solutions (Table 10); Figure 12 prints no values | AI R&D risk | |
| 7 Jul 2025 | | RE-Bench, 2.5 Flash 45-minute runs plotted in Figure 12 without printed values | AI R&D risk | |
| 28 Apr 2025 | | RE-Bench, 5 of 7 tasks: <= ~60% of human performance (Table 1), on average roughly 10-30% of human expert performance (text); Figure 4 prints no values | AI R&D risk | |
| 12 Sep 2024 | o1-preview system card | METR AI R&D Evaluations, normalized score on 7 environments, chart without printed numbers (Figure 5, 8.4) | AI R&D risk |
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