Claude Opus 4.5 Vision vs o4: which model should you choose?
We compared Claude Opus 4.5 Vision and o4 on price, context window and 12 benchmarks. Claude Opus 4.5 Vision has the stronger average benchmark score; o4 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
o4
o4 is a frontier model from OpenAI. It offers a 2,000,000-token context window, costs $17.74 per million input tokens and $66.00 per million output tokens, and averages 85.4 across the index's benchmark suite.
- Input
- $17.74 / 1M
- Output
- $66.00 / 1M
- Context
- 2,000,000
- Avg score
- 85.4
- Open weights
- No
Specification comparison
| Spec | Claude Opus 4.5 Vision | o4 | Edge |
|---|---|---|---|
| Input price / 1M | $17.70 | $17.74 | A |
| Output price / 1M | $74.84 | $66.00 | B |
| Context window | 200,000 | 2,000,000 | B |
| Max output | 32,768 | 8,192 | A |
| Average score | 85.9 | 85.4 | A |
| Arena Elo | 1452.2 | 1469.4 | B |
| Open weights | No | No | Tie |
Benchmark comparison
Claude Opus 4.5 Vision wins 7, o4 wins 5, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | Claude Opus 4.5 Vision | o4 | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 86.9 | 85.3 | 1.6 | Claude Opus 4.5 Vision |
| GPQA Diamond | 80.7 | 82.3 | 1.6 | o4 |
| SWE-bench Verified | 77.7 | 74.8 | 2.9 | Claude Opus 4.5 Vision |
| HumanEval | 88.2 | 89.6 | 1.4 | o4 |
| MATH-500 | 91.9 | 90.5 | 1.4 | Claude Opus 4.5 Vision |
| AIME 2025 | 85.4 | 85.3 | 0.1 | Claude Opus 4.5 Vision |
| LiveCodeBench | 80.1 | 81.4 | 1.3 | o4 |
| IFEval | 92.6 | 92.8 | 0.2 | o4 |
| TruthfulQA | 86.9 | 85.0 | 1.9 | Claude Opus 4.5 Vision |
| HellaSwag | 91.4 | 91.0 | 0.4 | Claude Opus 4.5 Vision |
| MMMU | 83.2 | 80.9 | 2.3 | Claude Opus 4.5 Vision |
| Arena Elo | 1452.2 | 1469.4 | 17.2 | o4 |
Price analysis
On a blended 3:1 input-to-output basis, Claude Opus 4.5 Vision costs about $31.98 per million tokens and o4 costs about $29.80. o4 is roughly 7% cheaper than Claude Opus 4.5 Vision. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.
o4 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 7, o4 wins 5, and 0 are tied. On the index average, Claude Opus 4.5 Vision leads o4 by 0.5 points (85.9 versus 85.4).
The price picture favours o4. The context picture favours o4. 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 o4 for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.
Choose Claude Opus 4.5 Vision if
- You want the higher average benchmark score in this index.
- You need the larger 32,768-token output limit.
Choose o4 if
- Unit cost matters and you want the cheaper blended price.
- You need the larger 2,000,000-token context window.
FAQ
Is Claude Opus 4.5 Vision better than o4?
On the index average, Claude Opus 4.5 Vision leads o4 by 0.5 points (85.9 versus 85.4). The better choice depends on price, context and your task. Claude Opus 4.5 Vision wins 7 benchmarks, o4 wins 5.
Which is cheaper, Claude Opus 4.5 Vision or o4?
o4 is cheaper on a blended 3:1 basis at about $29.80 per million tokens, versus $31.98 for Claude Opus 4.5 Vision.
Which has the larger context window?
o4 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; o4 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 o4 for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.