DeepResearch Bench
Agents write cited research reports for 100 PhD-level tasks across 22 fields. Judges score report quality against references and check citation accuracy.
The official judge model changed from Gemini 2.5 Pro to GPT-5.5 in May 2026, so older and newer scores do not compare directly.
In the authors’ words
Deep Research Agents are a prominent category of LLM-based agents. By autonomously orchestrating multistep web exploration, targeted retrieval, and higher-order synthesis, they transform vast amounts of online information into analyst-grade, citation-rich reports–compressing hours of manual desk research into minutes. However, a comprehensive benchmark for systematically evaluating the capabilities of these agents remains absent. To bridge this gap, we present DeepResearch Bench, a benchmark consisting of 100 PhD-level research tasks, each meticulously crafted by domain experts across 22 distinct fields. Evaluating DRAs is inherently complex and labor-intensive. We therefore propose two novel methodologies that achieve strong alignment with human judgment. The first is a reference-based method with adaptive criteria to assess the quality of generated research reports. The other framework is introduced to evaluate DRA's information retrieval and collection capabilities by assessing its effective citation count and overall citation accuracy. We have open-sourced DeepResearch Bench and key components of these frameworks at https://github.com/Ayanami0730/deep_research_bench to accelerate the development of practical LLM-based agents.
- Level
- Expert Specialists with years of training, often over hours of work
- Scored
- Graded by a model A language model scores each response, usually against a rubric.
- Answers
- Open-ended Free-form text, documents, designs or media judged as a whole.
Claude Opus 4.6 leads with 55.3% among models released by May 2026
Best score per model in Epoch AI’s data. Where a model ran with several settings or harnesses, we keep its best.
The newest model with a score here came out in May 2026, and nobody has tested a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:
- GPT-6 Astra
- Claude Opus 5.5
- GPT-6.1 Terra
- GPT-6.1 Sol
- and 14 more
- 55.3 Claude Opus 4.6
- 54.9 Claude Sonnet 4.6
- 54.8 Claude Opus 4.5
- 54.0 GPT-5.5
- 52.6 Claude Sonnet 4.5
- 50.2 Claude Opus 4.8
- 49.8
Gemini 3 Flash
- 49.6 GPT-5
- 48.3 Claude Opus 4.1
- 47.8
Gemini 3.1 Pro
- 47.3 Grok 4
- 46.8 Claude Opus 4
- 46.6 Claude Sonnet 4
- 46.3
Gemini 3 Pro
- 45.5 Claude Haiku 4.5
- 45.2 o3
- 43.6 Claude 3.7 Sonnet
- 42.8
Gemini 2.5 Pro
- 42.8 GPT-5.1
- 41.1 GPT-5.2
- 37.3
Gemini 3.1 Flash-Lite
- 36.3 GPT-5.4 Mini
- 35.1
DeepSeek-R1
- 35.1 GPT-5.4
- 1 Claude Opus 4.6 high 55.3%
- 2 Claude Sonnet 4.6 high 54.9%
- 3 Claude Opus 4.5 high 54.8%
- 4 GPT-5.5 high 54%
- 5 Claude Sonnet 4.5 2k thinking 52.6%
- 6 Claude Opus 4.8 high 50.2%
- 7
Gemini 3 Flash low 49.8%
- 8 GPT-5 low 49.6%
- 9 Claude Opus 4.1 48.3%
- 10
Gemini 3.1 Pro high 47.8%
- 11 Grok 4 47.3%
- 12 Claude Opus 4 2K 46.8%
- 13 Claude Sonnet 4 2K 46.6%
- 14
Gemini 3 Pro low 46.3%
- 15 Claude Haiku 4.5 low 45.5%
- 16 o3 medium 45.2%
- 17 Claude 3.7 Sonnet 2k thinking 43.6%
- 18
Gemini 2.5 Pro Jun 2025 42.8%
- 19 GPT-5.1 low 42.8%
- 20 GPT-5.2 low 41.1%
- 21
Gemini 3.1 Flash-Lite low 37.3%
- 22 GPT-5.4 Mini low 36.3%
- 23
DeepSeek-R1 May 2025 35.1%
- 24 GPT-5.4 low 35.1%
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude Opus 4.6 | 55.3% | high | Feb 2026 | Epoch AI |
| 2 | Claude Sonnet 4.6 | 54.9% | high | Feb 2026 | Epoch AI |
| 3 | Claude Opus 4.5 | 54.8% | high | Nov 2025 | Epoch AI |
| 4 | GPT-5.5 | 54% | high | Apr 2026 | Epoch AI |
| 5 | Claude Sonnet 4.5 | 52.6% | 2k thinking | Sep 2025 | Epoch AI |
| 6 | Claude Opus 4.8 | 50.2% | high | May 2026 | Epoch AI |
| 7 | | 49.8% | low | Dec 2025 | Epoch AI |
| 8 | GPT-5 | 49.6% | low | Aug 2025 | Epoch AI |
| 9 | Claude Opus 4.1 | 48.3% | Aug 2025 | Epoch AI | |
| 10 | | 47.8% | high | Feb 2026 | Epoch AI |
| 11 | Grok 4 | 47.3% | True | Jul 2025 | Epoch AI |
| 12 | Claude Opus 4 | 46.8% | 2K | May 2025 | Epoch AI |
| 13 | Claude Sonnet 4 | 46.6% | 2K | May 2025 | Epoch AI |
| 14 | | 46.3% | low | Nov 2025 | Epoch AI |
| 15 | Claude Haiku 4.5 | 45.5% | low | Oct 2025 | Epoch AI |
| 16 | o3 | 45.2% | medium | Apr 2025 | Epoch AI |
| 17 | Claude 3.7 Sonnet | 43.6% | 2k thinking | Feb 2025 | Epoch AI |
| 18 | | 42.8% | Jun 2025 | Epoch AI | |
| 19 | GPT-5.1 | 42.8% | low | Nov 2025 | Epoch AI |
| 20 | GPT-5.2 | 41.1% | low | Dec 2025 | Epoch AI |
| 21 | | 37.3% | low | Mar 2026 | Epoch AI |
| 22 | GPT-5.4 Mini | 36.3% | low | Mar 2026 | Epoch AI |
| 23 | | 35.1% | May 2025 | Epoch AI | |
| 24 | GPT-5.4 | 35.1% | low | Mar 2026 | Epoch AI |
The benchmark's own leaderboard has 43 entries, 4 of them models we track. Labs report scores for 2 models in their cards. We plot every source in the charts below.
2 models have held number one since its release in Jun 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, Epoch AI’s runs and what labs claim in their cards.
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Labs headline it less often now, last in Feb 2026
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 |
|---|---|---|---|
| 14 Feb 2026 | 53.3 | DeepResearchBench | |
| 18 Dec 2025 | 43.5 | DeepResearchBench | |
| 21 Aug 2025 | DeepResearch Bench RACE overall, English questions, Cohere's deep research agent powered by the model (chart only, about 48.6) |
2 system cards report it, from 1 lab
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 |
|---|---|---|---|---|
| 21 Mar 2026 | | 43.5 | DeepResearchBench (Table 4) | Capabilities |
| 14 Feb 2026 | | 53.3 | DeepResearchBench (Table 11) | Capabilities |
More in Tool use
- AutomationBench In use Agent completes end-to-end business workflows inside a simulated company exposing dozens of REST APIs. Graded on resulting state.
Gemini 4 Carbon 53.9%
- MCP Atlas In use Multi-step workflows over real MCP servers. Scores tool-use competency on realistic tasks.
Muse Spark 1.1 88.1%
- BFCL V4 In use Models call functions and tools, including multi-turn agentic tasks with web search and memory. Checked against expected calls and outcomes.
Qwen3.7-Max 75%
- τ³-bench Banking In use Agents act as banking customer-service reps over many turns with a simulated user, following policy. Pass^1 on the final database state.
Qwen 3.8 Max 55.1%
- Claw-Eval In use 300 human-verified agent tasks (service orchestration, multimodal, multi-turn dialogue) audited via traces and snapshots. Rubric scores with Pass^3 consistency. Claude Sonnet 4.6 81.4%
- DeepSearchQA In use Questions that need multi-step search and synthesis. Final answers graded against references. Kimi K3 95%