Benchmark Almanac

PaperBench Code-Dev

o1 43.4%
Not in model cards

Agents implement research paper code. The Code-Dev variant evaluates coding separately from full research replication.

The official README publishes a distinct Code-Dev result. This evaluation is not full PaperBench replication.

Made by
OpenAI
Released
April 2025
Kind
AI research tasks
Level
Research frontier
Scored
Graded by a model
Answers
Agent task
Tasks
All public
Strongest model tested
o1 #117 on the capability index
Last model added
December 2024
Scores refreshed
November 12th, 2026

In the authors’ words

We introduce PaperBench, a benchmark evaluating the ability of AI agents to replicate state-of-the-art AI research. Agents must replicate 20 ICML 2024 Spotlight and Oral papers from scratch, including understanding paper contributions, developing a codebase, and successfully executing experiments. For objective evaluation, we develop rubrics that hierarchically decompose each replication task into smaller sub-tasks with clear grading criteria. In total, PaperBench contains 8,316 individually gradable tasks. Rubrics are co-developed with the author(s) of each ICML paper for accuracy and realism. To enable scalable evaluation, we also develop an LLM-based judge to automatically grade replication attempts against rubrics, and assess our judge's performance by creating a separate benchmark for judges. We evaluate several frontier models on PaperBench, finding that the best-performing tested agent, Claude 3.5 Sonnet (New) with open-source scaffolding, achieves an average replication score of 21.0%. Finally, we recruit top ML PhDs to attempt a subset of PaperBench, finding that models do not yet outperform the human baseline. We open-source our code (https://github.com/openai/preparedness) to facilitate future research in understanding the AI engineering capabilities of AI agents.

Abstract of PaperBench: Evaluating AI's Ability to Replicate AI Research (arXiv:2504.01848, CC0)
1
Model scored on its own leaderboard

o1 leads with 43.4%

Best score per model from the benchmark's own leaderboard, read on November 12th, 2026. Where a model ran with several settings or harnesses, we keep its best.

  1. 1 o1 PaperBench Code-Dev; high 43.4%

Source: Official PaperBench Code-Dev leaderboard

#ModelScoreSettingDateSource
1 o1 43.4% PaperBench Code-Dev; high, IterativeAgent Dec 2024 Official leaderboard

Scores over time

All the scores we have, one dot each, so a model tested at several settings appears more than once.

On the benchmark’s own leaderboard
0% 20% 40% 60% 80% 100% 2025 Near the ceiling (85%) o1 0% 20% 40% 60% 80% 100% 2025 Near the ceiling (85%) o1

Source: Official PaperBench Code-Dev leaderboard

No lab model card reports it yet

We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark.

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