AceBench
Models call tools from 4,538 Chinese and English APIs in normal, special, and multi-turn agent cases. Answers are checked without LLM judges or live APIs.
- Made by
- Chen Chen et al.
- Released
- January 2025
- Kind
- Function calling
- Level
- Everyday
- Scored
- Checked automatically
- Answers
- Short answer
- Tasks
- All public
- Strongest model tested
- Kimi K2 Jul 2025 #116 on the capability index
- Last in a launch post
- February 2026, dropped after it saturated
- Last model added
- February 2026
- Scores refreshed
- November 12th, 2026
In the authors’ words
Large Language Models (LLMs) have demonstrated significant potential in decision-making and reasoning, particularly when integrated with various tools to effectively solve complex problems. However, existing benchmarks for evaluating LLMs' tool usage face several limitations: (1) limited evaluation scenarios, often lacking assessments in real multi-turn dialogue contexts; (2) narrow evaluation dimensions, with insufficient detailed assessments of how LLMs use tools; and (3) reliance on LLMs or real API executions for evaluation, which introduces significant overhead. To address these challenges, we introduce ACEBench, a comprehensive benchmark for assessing tool usage in LLMs. ACEBench categorizes data into three primary types based on evaluation methodology: Normal, Special, and Agent. "Normal" evaluates tool usage in basic scenarios; "Special" evaluates tool usage in situations with ambiguous or incomplete instructions; "Agent" evaluates tool usage through multi-agent interactions to simulate real-world, multi-turn dialogues. We conducted extensive experiments using ACEBench, analyzing various LLMs in-depth and providing a more granular examination of error causes across different data types.
GPT-4o leads with 85.4% among models released by July 2025
Best score per entry from the benchmark's own leaderboard, read on November 12th, 2026. Where a model ran with several settings or harnesses, we keep its best. Names in gray aren't in our model list: fine-tunes, agent systems, products and older models. They don't count toward leaders.
ERNIE 5.0 leads with 88.7%, 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.
The newest model with a score here came out in July 2025, and nobody has tested a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:
- Claude Fable 5.2
-
Gemini 4 Carbon
- GPT-6 Astra
- Claude Opus 5.5
- and 16 more
- 85.4 GPT-4o
- 82.2 Kimi K2
- 80.6
Gemini 2.5 Pro
- 79.6
Qwen2.5-Coder-32B-Instruct
- 78.4 Qwen-Max
- 74.8
DeepSeek-V3
- 74.7
Qwen2.5-72B
- 72.5 GPT-4o mini
- 72.2 ToolACE-2.5-Llama-3.1-8B
- 70.7
Gemini 1.5 Pro
- 68.9 Claude 3.5 Sonnet
- 60.4
Llama 3.1-70B
- 59.4 Doubao-Pro-32K
- 54.8
Qwen2.5-7B
- 49.5 DeepSeek-Coder-V2-Lite-Instruct
- 48.9
Qwen2.5-Coder (7B)
- 45.7 Watt-Tool-8B
- 42.9 Hammer2.1-7B
- 33.4
Llama 3.1-8B
- 32.0
Phi-3-mini-128k-instruct
- 21.6 xLAM-7b-r
- 19.6
Llama 3.2 3B
- 11.3 Hammer2.1-3B
- 1 GPT-4o Nov 2024 85.4%
- 2 Kimi K2 Jul 2025 82.2%
- 3
Gemini 2.5 Pro May 2025 80.6%
- 4
Qwen2.5-Coder-32B-Instruct 79.6%
- 5 Qwen-Max 78.4%
- 6
DeepSeek-V3 74.8%
- 7
Qwen2.5-72B 74.7%
- 8 GPT-4o mini 72.5%
- 9 ToolACE-2.5-Llama-3.1-8B 72.2%
- 10
Gemini 1.5 Pro Sep 2024 70.7%
- 11 Claude 3.5 Sonnet 68.9%
- 12
Llama 3.1-70B 60.4%
- 13 Doubao-Pro-32K 59.4%
- 14
Qwen2.5-7B 54.8%
- 15 DeepSeek-Coder-V2-Lite-Instruct 49.5%
- 16
Qwen2.5-Coder (7B) 48.9%
- 17 Watt-Tool-8B 45.7%
- 18 Hammer2.1-7B 42.9%
- 19
Llama 3.1-8B 33.4%
- 20
Phi-3-mini-128k-instruct 32%
- 21 xLAM-7b-r 21.6%
- 22
Llama 3.2 3B 19.6%
- 23 Hammer2.1-3B 11.3%
Source: Official AceBench leaderboard
- 88.7
ERNIE 5.0
- 85.4 GPT-4o
- 82.2 Kimi K2
- 80.6
Gemini 2.5 Pro
- 79.6
Qwen2.5-Coder-32B-Instruct
- 76.1
LongCat-Flash-Chat
- 74.8
DeepSeek-V3
- 74.7
Qwen2.5-72B
- 72.5 GPT-4o mini
- 70.7
Gemini 1.5 Pro
- 68.9 Claude 3.5 Sonnet
- 60.4
Llama 3.1-70B
- 54.8
Qwen2.5-7B
- 49.5 DeepSeek-Coder-V2-Lite-Instruct
- 48.9
Qwen2.5-Coder (7B)
- 33.4
Llama 3.1-8B
- 32.0
Phi-3-mini-128k-instruct
- 19.6
Llama 3.2 3B
- 1
ERNIE 5.0 88.7%
- 2 GPT-4o Nov 2024 85.4%
- 3 Kimi K2 Jul 2025 82.2%
- 4
Gemini 2.5 Pro May 2025 80.6%
- 5
Qwen2.5-Coder-32B-Instruct 79.6%
- 6
LongCat-Flash-Chat 76.1%
- 7
DeepSeek-V3 74.8%
- 8
Qwen2.5-72B 74.7%
- 9 GPT-4o mini 72.5%
- 10
Gemini 1.5 Pro Sep 2024 70.7%
- 11 Claude 3.5 Sonnet 68.9%
- 12
Llama 3.1-70B 60.4%
- 13
Qwen2.5-7B 54.8%
- 14 DeepSeek-Coder-V2-Lite-Instruct 49.5%
- 15
Qwen2.5-Coder (7B) 48.9%
- 16
Llama 3.1-8B 33.4%
- 17
Phi-3-mini-128k-instruct 32%
- 18
Llama 3.2 3B 19.6%
Sources: Labs’ model cards and official AceBench leaderboard
| # | Entry | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | GPT-4o Nov 2024 | 85.4% | Nov 2024 | Official leaderboard | |
| 2 | Kimi K2 Jul 2025 | 82.2% | Jul 2025 | Official leaderboard | |
| 3 | | 80.6% | May 2025 | Official leaderboard | |
| 4 | | 79.6% | Nov 2024 | Official leaderboard | |
| 5 | Qwen-Max | 78.4% | Jan 2025 | Official leaderboard | |
| 6 | | 74.8% | Dec 2024 | Official leaderboard | |
| 7 | | 74.7% | Sep 2024 | Official leaderboard | |
| 8 | GPT-4o mini | 72.5% | Jul 2024 | Official leaderboard | |
| 9 | ToolACE-2.5-Llama-3.1-8B | 72.2% | Jan 2025 | Official leaderboard | |
| 10 | | 70.7% | Sep 2024 | Official leaderboard | |
| 11 | Claude 3.5 Sonnet | 68.9% | Jun 2024 | Official leaderboard | |
| 12 | | 60.4% | Jul 2024 | Official leaderboard | |
| 13 | Doubao-Pro-32K | 59.4% | Jan 2025 | Official leaderboard | |
| 14 | | 54.8% | Sep 2024 | Official leaderboard | |
| 15 | DeepSeek-Coder-V2-Lite-Instruct | 49.5% | Jun 2024 | Official leaderboard | |
| 16 | | 48.9% | Sep 2024 | Official leaderboard | |
| 17 | Watt-Tool-8B | 45.7% | Jan 2025 | Official leaderboard | |
| 18 | Hammer2.1-7B | 42.9% | Jan 2025 | Official leaderboard | |
| 19 | | 33.4% | Jul 2024 | Official leaderboard | |
| 20 | | 32% | Apr 2024 | Official leaderboard | |
| 21 | xLAM-7b-r | 21.6% | Jan 2025 | Official leaderboard | |
| 22 | | 19.6% | Sep 2024 | Official leaderboard | |
| 23 | Hammer2.1-3B | 11.3% | Jan 2025 | Official leaderboard |
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | | 88.7% | Feb 2026 | Lab model card | |
| 2 | GPT-4o Nov 2024 | 85.4% | Nov 2024 | Official leaderboard | |
| 3 | Kimi K2 Jul 2025 | 82.2% | Jul 2025 | Official leaderboard | |
| 4 | | 80.6% | May 2025 | Official leaderboard | |
| 5 | | 79.6% | Nov 2024 | Official leaderboard | |
| 6 | | 76.1% | Aug 2025 | Lab model card | |
| 7 | | 74.8% | Dec 2024 | Official leaderboard | |
| 8 | | 74.7% | Sep 2024 | Official leaderboard | |
| 9 | GPT-4o mini | 72.5% | Jul 2024 | Official leaderboard | |
| 10 | | 70.7% | Sep 2024 | Official leaderboard | |
| 11 | Claude 3.5 Sonnet | 68.9% | Jun 2024 | Official leaderboard | |
| 12 | | 60.4% | Jul 2024 | Official leaderboard | |
| 13 | | 54.8% | Sep 2024 | Official leaderboard | |
| 14 | DeepSeek-Coder-V2-Lite-Instruct | 49.5% | Jun 2024 | Official leaderboard | |
| 15 | | 48.9% | Sep 2024 | Official leaderboard | |
| 16 | | 33.4% | Jul 2024 | Official leaderboard | |
| 17 | | 32% | Apr 2024 | Official leaderboard | |
| 18 | | 19.6% | Sep 2024 | Official leaderboard |
Labs report scores for 3 models in their cards. Switch the scores above to rank them together.
Number one over time 2 models have held number one with claims included since its release in January 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.
GPT-4o on the official leaderboard passed 85% in November 2024
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Sources: Official AceBench leaderboard and labs’ model cards
Labs headline it less often now, last in February 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 |
|---|---|---|---|
| Feb 6, 2026 | 88.7 | Mean of ACEBench-en 87.70 / ACEBench-zh 89.60 | |
| Aug 29, 2025 | 76.1 | AceBench(acc) | |
| Jul 11, 2025 | Kimi K2 | 76.5 | AceBench, Acc |
3 system cards report it, from 3 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 |
|---|---|---|---|---|
| Feb 4, 2026 | | ACEBench-en 87.70, ACEBench-zh 89.60, no overall score (Table 2) | Capabilities | |
| Sep 1, 2025 | | 76.1 | AceBench (acc), direct prompting (Table 3) | Capabilities |
| Jul 21, 2025 | Kimi K2 technical report | 76.5 | AceBench (Acc.), ACEBench English overall (Table 3) | Capabilities |
One lab claim next to the leaderboard
Each score a lab reported for its own model, beside the same model's best score on the leaderboard. Gaps mostly come from different harnesses, effort levels and task subsets. Every benchmark.
| Model | Lab says | Board says | Gap |
|---|---|---|---|
| Kimi K2 Jul 2025 | 76.5% AceBench, Acc | 82.2% Leaderboard | −5.7 pts |
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