PaperBench
Agent replicates ICML 2024 papers from scratch. LLM judge grades against author-written hierarchical rubrics.
Repo renamed from openai/preparedness. Qwen and MiniMax use different judges (Opus 4.6) and 12h runs, so scores are not comparable.
- 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
-
Qwen 3.8 Max #29 on the capability index
- Last in a launch post
- November 2026
- Last model added
- November 2026
- 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.
Qwen 3.8 Max leads with 93%
Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.
o1 leads with 26% across all independent runs
Best score per model across the official leaderboard, Epoch AI’s own runs and any board Epoch AI copied. Each bar and row names its source.
Qwen 3.8 Max leads with 93%, claims included
Best score per model from every source, including labs’ own numbers and claims Epoch AI collected from reports and papers. Labs pick their own settings, so a claim can beat an independent run of the same model.
- 1
Qwen 3.8 Max 93%
- 2
LongCat-2.5 82.1%
- 3 Kimi K2.5 63.5%
- 4
MiniMax-M3 52.6%
- 5
Seed2.0 Lite (0428) 52.5%
- 6 GPT-5.2 Codex 43%
- 7 GPT-5.1-Codex-Max 40%
- 8 GPT-5.2 39%
- 9 Kimi K2 Jul 2025 27.8%
- 10 o4-mini 25%
- 11 GPT-5 24%
- 12 GPT-5 mini 23%
- 13 o3 18%
- 14 gpt-oss-120b 11%
- 15 gpt-oss-20b 7.00%
Source: Labs’ model cards
- 1 o1 PaperBench; high; 36h limit 26%
- 2 o3-mini PaperBench; high 8.50%
- 3
DeepSeek-R1 PaperBench 6.00%
Source: Official PaperBench leaderboard
- 1
Qwen 3.8 Max 93%
- 2
LongCat-2.5 82.1%
- 3 Kimi K2.5 63.5%
- 4
MiniMax-M3 52.6%
- 5
Seed2.0 Lite (0428) 52.5%
- 6 GPT-5.2 Codex 43%
- 7 GPT-5.1-Codex-Max 40%
- 8 GPT-5.2 39%
- 9 Kimi K2 Jul 2025 27.8%
- 10 o1 PaperBench; high; 36h limit 26%
- 11 o4-mini 25%
- 12 GPT-5 24%
- 13 GPT-5 mini 23%
- 14 o3 18%
- 15 gpt-oss-120b 11%
- 16 o3-mini PaperBench; high 8.50%
- 17 gpt-oss-20b 7.00%
- 18
DeepSeek-R1 PaperBench 6.00%
Sources: Labs’ model cards and official PaperBench leaderboard
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | | 93% | Aug 2026 | Lab model card | |
| 2 | | 82.1% | Nov 2026 | Lab model card | |
| 3 | Kimi K2.5 | 63.5% | Jan 2026 | Lab model card | |
| 4 | | 52.6% | Jun 2026 | Lab model card | |
| 5 | | 52.5% | Apr 2026 | Lab model card | |
| 6 | GPT-5.2 Codex | 43% | Dec 2025 | Lab model card | |
| 7 | GPT-5.1-Codex-Max | 40% | Nov 2025 | Lab model card | |
| 8 | GPT-5.2 | 39% | Dec 2025 | Lab model card | |
| 9 | Kimi K2 Jul 2025 | 27.8% | Jul 2025 | Lab model card | |
| 10 | o4-mini | 25% | Apr 2025 | Lab model card | |
| 11 | GPT-5 | 24% | Aug 2025 | Lab model card | |
| 12 | GPT-5 mini | 23% | Aug 2025 | Lab model card | |
| 13 | o3 | 18% | Apr 2025 | Lab model card | |
| 14 | gpt-oss-120b | 11% | Aug 2025 | Lab model card | |
| 15 | gpt-oss-20b | 7.00% | Aug 2025 | Lab model card |
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | o1 | 26% | PaperBench; high; 36h limit, IterativeAgent | Dec 2024 | Official leaderboard |
| 2 | o3-mini | 8.50% | PaperBench; high, IterativeAgent | Jan 2025 | Official leaderboard |
| 3 | | 6.00% | PaperBench, BasicAgent | Jan 2025 | Official leaderboard |
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | | 93% | Aug 2026 | Lab model card | |
| 2 | | 82.1% | Nov 2026 | Lab model card | |
| 3 | Kimi K2.5 | 63.5% | Jan 2026 | Lab model card | |
| 4 | | 52.6% | Jun 2026 | Lab model card | |
| 5 | | 52.5% | Apr 2026 | Lab model card | |
| 6 | GPT-5.2 Codex | 43% | Dec 2025 | Lab model card | |
| 7 | GPT-5.1-Codex-Max | 40% | Nov 2025 | Lab model card | |
| 8 | GPT-5.2 | 39% | Dec 2025 | Lab model card | |
| 9 | Kimi K2 Jul 2025 | 27.8% | Jul 2025 | Lab model card | |
| 10 | o1 | 26% | PaperBench; high; 36h limit, IterativeAgent | Dec 2024 | Official leaderboard |
| 11 | o4-mini | 25% | Apr 2025 | Lab model card | |
| 12 | GPT-5 | 24% | Aug 2025 | Lab model card | |
| 13 | GPT-5 mini | 23% | Aug 2025 | Lab model card | |
| 14 | o3 | 18% | Apr 2025 | Lab model card | |
| 15 | gpt-oss-120b | 11% | Aug 2025 | Lab model card | |
| 16 | o3-mini | 8.50% | PaperBench; high, IterativeAgent | Jan 2025 | Official leaderboard |
| 17 | gpt-oss-20b | 7.00% | Aug 2025 | Lab model card | |
| 18 | | 6.00% | PaperBench, BasicAgent | Jan 2025 | Official leaderboard |
The benchmark's own leaderboard has 6 entries, 3 of them models we track. Switch the scores above to rank them together.
6 models have held number one in labs’ own numbers since its release in April 2025 Number one over time 6 models have held number one with claims included since its release in April 2025
Lab claims count from the day the card came out, independent runs from the model’s release. We draw one row each for the benchmark’s own leaderboard and what labs claim in their cards.
Sources: Official PaperBench leaderboard and labs’ model cards
Qwen’s own number for Qwen 3.8 Max passed 85% in August 2026
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Sources: Official PaperBench leaderboard and labs’ model cards
3 labs put it in a launch post in the last six months
Launch posts from every lab that has listed it, one tick per post. Tall colored ticks include it, and short gray ones leave it out.
| Date | Launch post | Score | As the post writes it |
|---|---|---|---|
| Nov 2, 2026 | 82.1 | PaperBench | |
| Aug 3, 2026 | 93 | PaperBench | |
| Jun 1, 2026 | 52.6 | PaperBench | |
| Apr 28, 2026 | 52.5 | PaperBench | |
| Jan 27, 2026 | Kimi K2.5 | 63.5 | PaperBench |
12 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 |
|---|---|---|---|---|
| Jan 30, 2026 | Kimi K2.5 technical report | 63.5 | PaperBench (CodeDev) (Table 4) | AI R&D risk |
| Dec 18, 2025 | GPT-5.2 Codex system card addendum | 43 | PaperBench (no browsing), 10-paper subset, pass@1, Extra High reasoning effort, printed chart label (Figure 11, 5.1.3.3) | AI R&D risk |
| Dec 11, 2025 | GPT-5.2 system card addendum | 39 | PaperBench (no browsing), 10-paper subset, pass@1, high reasoning effort, printed chart label (Figure 15) | AI R&D risk |
| Nov 18, 2025 | GPT-5.1-Codex-Max system card | 40 | PaperBench (no browsing), 10-paper subset, pass@1, Extra High reasoning effort, printed chart label (Figure 9, 5.1.3.2) | AI R&D risk |
| Aug 7, 2025 | GPT-5 system card | 24 | PaperBench 10-paper subset (no browsing), pass@1, launch candidate (Figure 25) | AI R&D risk |
| Aug 7, 2025 | GPT-5 mini system card | 23 | PaperBench 10-paper subset (no browsing), pass@1, gpt-5-thinking-mini launch candidate (Figure 25) | AI R&D risk |
| Aug 5, 2025 | gpt-oss-20b model card | 7 | PaperBench 10-paper subset (no browsing), pass@1, gpt-oss 20b launch candidate (Figure 16) | AI R&D risk |
| Aug 5, 2025 | gpt-oss-120b model card | 11 | PaperBench 10-paper subset (no browsing), pass@1, gpt-oss 120b launch candidate (Figure 16) | AI R&D risk |
| Jul 21, 2025 | Kimi K2 technical report | 27.8 | Paper Bench Code-Dev (Acc.) (Table 3) | AI R&D risk |
| Jul 17, 2025 | ChatGPT agent system card | PaperBench (no browsing), 10-paper subset, pass@1, chart shows only ChatGPT Agent no-browsing helpful-only at 22%, no released-model value (Figure 18, 5.1.3.4) | AI R&D risk | |
| Apr 16, 2025 | o4-mini system card | 25 | PaperBench (no browsing), pass@1, high reasoning effort, o4-mini no browsing launch candidate, printed chart label (Figure 23), text says 24% | AI R&D risk |
| Apr 16, 2025 | o3 system card | 18 | PaperBench (no browsing), pass@1, high reasoning effort, o3 no browsing launch candidate, printed chart label (Figure 23) | AI R&D risk |
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