Multimodal Large Language Models (MLLMs) have demonstrated strong abilities in solving diverse visual and textual reasoning tasks. However, their development in the physics domain is significantly hindered by the lack of a comprehensive benchmark. To fill this gap, we introduce OmniPhys, a large-scale benchmark for multimodal physics understanding and reasoning, covering middle school through university-level problems from Chinese Educational Corpora. OmniPhys consists of 15,246 questions and 19,850 images, accompanied by detailed annotations that support fine-grained analysis of reasoning processes and knowledge usage. Beyond conventional evaluation, OmniPhys is a benchmark that systematically evaluates multimodal outputs in the physics domain, including models' ability to generate structured physics diagrams, which constitute a fundamental component of authentic physics problem solving. Extensive evaluations reveal critical gaps in the capabilities of current MLLMs, especially in complex reasoning and visual generation. To address this, we release OmniPhys to serve as a foundational resource for advancing multimodal intelligence in physics and scientific domains. Codes and data are available at https://github.com/ECNU-RAIL/OmniPhys-EMNLP2026.
Figures & tables
Figure 1: Overview of the OmniPhys Dataset. The benchmark encompasses five major physics disciplines, illustrated by representative samples: Mechanics , Electromagnetism , Optics , Thermodynamics , and Acoustics .
Dataset
Size (Phys.)
Lang.
Education Stage
Image Modality
Overlap
PS
MS
HS
Uni
Input
Output
Text-Only Benchmarks
PhysQA Ding et al. (2023)
1,008
EN
✗
✓
✗
✗
✗
✗
0.00%
C-Eval Huang et al. (2023)
601
ZH
✗
✓
✓
✓
✗
✗
0.00%
MMLU Hendrycks et al. (2020)
548
EN
✗
✗
✓
✓
✗
✗
0.00%
GAOKAO Zhang et al. (2023)
111
ZH
✗
✗
✓
✗
✗
✗
0.00%
Table 1: Comparison with Existing Physics Datasets. OmniPhys distinguishes itself by supporting multimodal outputs and covering the full spectrum of educational stages. (Lang.: Language, PS: Primary School, MS: Middle School, HS: High School, Uni: University) Overlap (rightmost column) indicates the percentage of samples in OmniPhys that overlap with existing benchmarks, computed via string similarity and perceptual hashing. Our dataset maintains near-zero overlap while uniquely supporting multimodal outputs across all stages.
Category
Count
Physics Domains
Mechanics
7,240
Electromagnetism
5,325
Optics
1,120
Thermodynamics
856
Acoustics
705
Table 2: Statistics of OmniPhys. The benchmark maintains a high-quality distribution across three educational stages. In response to the growing need for generative AI, we specifically curated a subset for Multimodal Generation , featuring expert-annotated diagrams.
Model
Acoustics
Optics
Mechanics
Thermodynamics
Electricity
Overall
S1
S2
S3
S1
S2
S3
S1
S2
S3
S1
S2
S3
S1
S2
S3
S1
S2
S3
Pobj
Popen
Proprietary / Closed-source MLLMs
GPT-5.2
67.48
81.65
67.78
65.15
79.73
64.42
66.33
79.67
72.30
69.89
82.13
73.84
60.15
77.05
66.34
64.15
78.85
69.42
39.36
29.45
GPT-5.1
58.68
72.24
55.40
52.77
66.09
49.32
52.30
67.91
54.47
59.87
73.50
52.04
45.48
64.07
50.95
50.25
66.68
52.59
23.53
12.87
GPT-4o
46.21
64.07
47.36
41.15
55.99
35.03
39.41
54.01
40.33
49.02
60.46
46.76
36.63
52.24
38.28
39.04
53.93
39.50
12.28
4.61
o4-mini
62.39
68.86
58.46
59.19
67.79
49.08
64.85
72.01
60.01
70.76
77.39
63.86
59.55
67.78
52.63
62.75
70.36
56.48
39.34
21.50
Table 3: Main Results on OmniPhys. Metrics: S1 (Answer Accuracy), S2 / S3 (Process Quality for Objective/Open-ended tasks), and Pobj , Popen (Strict Mastery Rates). Formatting : In each section (Closed-source MLLMs/Open-source MLLMs), the best score is bolded and the second best is underlined. The global best across all models is highlighted in blue .
Figure 2: Performance Degradation Across Educational Stages. We report the pass rates (%) of 12 representative MLLMs across Junior High, Senior High, and University levels. Both closed-source (Left) and open-source (Right) models exhibit a consistent downward trend, validating the hierarchical difficulty design of OmniPhys.
Model
Evaluation Scores
Human Eval.
Model Eval.
Nano Banana
0.23
0.67
Doubao-Seedream-4.0
0.18
0.59
Gemini-3-pro-Image
0.29
0.73
GPT-Image-1
0.27
0.75
Qwen-Image-Edit-Plus
0.10
0.51
Table 4: Performance comparison in multimodal output settings.
Figure 3: A case study of multimodal outputs in OmniPhys dataset.
Model
Full Set
Test-Mini
Drop
Doubao-seed-1.6
76.81
22.45
-70.8%
Gemini-3-pro
80.41
34.66
-56.9%
GLM-4.6v
71.12
19.90
-72.0%
GPT-5.2
65.60
21.82
-66.7%
Qwen3-vl-plus
68.24
18.76
-72.5%
Average
72.44
23.52
-67.8%
Table 5: Comparison of Average Scores (scaled to 0-100) on the full dataset versus the Test-Mini set. The significant score decline (avg. -67.8%) confirms the elevated difficulty of the subset, validating its distinct research value as a rigorous probe for robust physical reasoning.
Multimodal Large Language Models (MLLMs)
Large Language Models (LLMs)
Model
Text+Img
Text+Caption
Text-only
Model
Text+Caption
Text-only
Pobj
Popen
Pobj
Popen
Pobj
Popen
Pobj
Popen
Pobj
Popen
GPT-5.2
2.78
3.02
4.95
1.08
5.82
0.86
Deepseek-V3.2
5.58
1.08
5.70
1.73
GPT-5.1
2.55
1.08
4.00
0.86
2.55
1.08
GPT-3.5-Turbo
1.94
0.63
1.45
0.22
o4-mini
7.23
1.96
6.55
0.86
6.79
1.73
Qwen2.5-32B
3.64
0.02
3.24
0.22
Gemini-3-Pro
25.82
9.50
16.12
4.10
15.88
6.26
Qwen2.5-7B
1.82
0.05
0.97
0.05
Table 6: Ablation study results comparing MLLMs (left) and LLMs (right). The columns are arranged by decreasing modal information: from Text+Image to Text-only. We report Objective ( Pobj ) and Open-ended ( Popen ) Accuracy.
Appendix figures & tables7 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 4: Screenshot of the Label Studio interface for human evaluation of multimodal outputs.
Metric
Full Set
Test-Mini
Sample Size
12,885
1,288
Avg. Reasoning Length (chars)
563
979
Visual Necessity Score
8.98
8.99
All-Model Failure Rate
1.6%
15.5%
Avg. Model Accuracy
72.44%
23.52%
Appendix
Table 7: Comparison of key statistics between the full dataset and the selected Test-Mini subset. The subset demonstrates significantly higher complexity and lower model solvability.
Filtering Task
Metric
Human-Human
Human-Machine
Visual Dependency
Agreement (%)
92.6%
89.3%
Cohen’s κ
0.86
0.82
Difficulty Screening
Agreement (%)
94.1%
91.5%
Cohen’s κ
0.88
0.84
Appendix
Table 8: Alignment Statistics for Data Refinement. The "Human-Machine" column represents the consistency between our automated pipeline (using MLLMs and vLLM) and expert consensus. Scores above 0.80 signify strong reliability in our data quality control.
Metric
Pearson r
Spearman ρ
Agreement (%)
Δ Score
S1 (Answer Accuracy)
0.89
0.87
92.4%
+1.2%
S2 (Obj. Process)
0.86
0.84
89.7%
+2.5%
S3 (Subj. Process)
0.82
0.81
85.5%
+4.2%
Pobj (Mastery)
0.92
0.91
93.1%
+0.8%
Popen (Mastery)
0.88
0.86
91.2%
+1.5%
Appendix
Table 9: Human-Machine Alignment Results. Comparison between expert consensus and the LLM-as-a-Judge framework across primary metrics. Δ Score represents the mean difference (Machine − Human).
Figure 5: A middle school, Mechanics example of Original Physics Problems.
Figure 6: A high school, Electromagnetism example of Original Physics Problems.
Figure 7: A University, Optics example of Original Physics Problems.