Claude Opus 4.5 Vision vs o3 Max: which model should you choose?
We compared Claude Opus 4.5 Vision and o3 Max on price, context window and 12 benchmarks. Claude Opus 4.5 Vision has the stronger average benchmark score; Claude Opus 4.5 Vision is cheaper on a blended 3:1 basis.
Claude Opus 4.5 Vision
Claude Opus 4.5 Vision is a frontier model from Anthropic. It offers a 200,000-token context window, costs $17.70 per million input tokens and $74.84 per million output tokens, and averages 85.9 across the index's benchmark suite.
- Input
- $17.70 / 1M
- Output
- $74.84 / 1M
- Context
- 200,000
- Avg score
- 85.9
- Open weights
- No
o3 Max
o3 Max is a frontier model from OpenAI. It offers a 2,000,000-token context window, costs $17.82 per million input tokens and $90.55 per million output tokens, and averages 84.8 across the index's benchmark suite.
- Input
- $17.82 / 1M
- Output
- $90.55 / 1M
- Context
- 2,000,000
- Avg score
- 84.8
- Open weights
- No
Specification comparison
| Spec | Claude Opus 4.5 Vision | o3 Max | Edge |
|---|---|---|---|
| Input price / 1M | $17.70 | $17.82 | A |
| Output price / 1M | $74.84 | $90.55 | A |
| Context window | 200,000 | 2,000,000 | B |
| Max output | 32,768 | 128,000 | B |
| Average score | 85.9 | 84.8 | A |
| Arena Elo | 1452.2 | 1465.2 | B |
| Open weights | No | No | Tie |
Benchmark comparison
Claude Opus 4.5 Vision wins 6, o3 Max wins 6, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | Claude Opus 4.5 Vision | o3 Max | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 86.9 | 84.9 | 2.0 | Claude Opus 4.5 Vision |
| GPQA Diamond | 80.7 | 82.7 | 2.0 | o3 Max |
| SWE-bench Verified | 77.7 | 71.8 | 5.9 | Claude Opus 4.5 Vision |
| HumanEval | 88.2 | 89.8 | 1.6 | o3 Max |
| MATH-500 | 91.9 | 87.0 | 4.9 | Claude Opus 4.5 Vision |
| AIME 2025 | 85.4 | 86.2 | 0.8 | o3 Max |
| LiveCodeBench | 80.1 | 76.4 | 3.7 | Claude Opus 4.5 Vision |
| IFEval | 92.6 | 92.5 | 0.1 | Claude Opus 4.5 Vision |
| TruthfulQA | 86.9 | 87.3 | 0.4 | o3 Max |
| HellaSwag | 91.4 | 93.4 | 2.0 | o3 Max |
| MMMU | 83.2 | 80.8 | 2.4 | Claude Opus 4.5 Vision |
| Arena Elo | 1452.2 | 1465.2 | 13.0 | o3 Max |
Price analysis
On a blended 3:1 input-to-output basis, Claude Opus 4.5 Vision costs about $31.98 per million tokens and o3 Max costs about $36.00. Claude Opus 4.5 Vision is roughly 11% cheaper than o3 Max. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.
o3 Max has the larger context window at 2,000,000 tokens, compared with 200,000 for Claude Opus 4.5 Vision. That matters for long documents, large codebases and multi-step agent traces.
Verdict
Across 12 shared benchmarks, Claude Opus 4.5 Vision wins 6, o3 Max wins 6, and 0 are tied. On the index average, Claude Opus 4.5 Vision leads o3 Max by 1.1 points (85.9 versus 84.8).
The price picture favours Claude Opus 4.5 Vision. The context picture favours o3 Max. Those two dimensions often matter more than a few benchmark points once a model is good enough for the task.
If you need a single default, start with Claude Opus 4.5 Vision for quality-sensitive work, and check whether its price holds at your expected volume before committing.
Choose Claude Opus 4.5 Vision if
- You want the higher average benchmark score in this index.
- Unit cost matters and you want the cheaper blended price.
Choose o3 Max if
- You need the larger 2,000,000-token context window.
- You need the larger 128,000-token output limit.
FAQ
Is Claude Opus 4.5 Vision better than o3 Max?
On the index average, Claude Opus 4.5 Vision leads o3 Max by 1.1 points (85.9 versus 84.8). The better choice depends on price, context and your task. Claude Opus 4.5 Vision wins 6 benchmarks, o3 Max wins 6.
Which is cheaper, Claude Opus 4.5 Vision or o3 Max?
Claude Opus 4.5 Vision is cheaper on a blended 3:1 basis at about $31.98 per million tokens, versus $36.00 for o3 Max.
Which has the larger context window?
o3 Max has the larger context window at 2,000,000 tokens. Claude Opus 4.5 Vision has 200,000 tokens.
Are these models open weights?
Claude Opus 4.5 Vision is proprietary; o3 Max is proprietary.
Which should I choose for production?
If you need a single default, start with Claude Opus 4.5 Vision for quality-sensitive work, and check whether its price holds at your expected volume before committing.