GPT-5.1 Vision vs Grok 3 Max: which model should you choose?
We compared GPT-5.1 Vision and Grok 3 Max on price, context window and 12 benchmarks. Grok 3 Max has the stronger average benchmark score; GPT-5.1 Vision is cheaper on a blended 3:1 basis.
GPT-5.1 Vision
GPT-5.1 Vision is a frontier model from OpenAI. It offers a 400,000-token context window, costs $17.76 per million input tokens and $80.59 per million output tokens, and averages 84.8 across the index's benchmark suite.
- Input
- $17.76 / 1M
- Output
- $80.59 / 1M
- Context
- 400,000
- Avg score
- 84.8
- Open weights
- No
Grok 3 Max
Grok 3 Max is a frontier model from xAI. It offers a 2,000,000-token context window, costs $17.66 per million input tokens and $89.12 per million output tokens, and averages 85.9 across the index's benchmark suite.
- Input
- $17.66 / 1M
- Output
- $89.12 / 1M
- Context
- 2,000,000
- Avg score
- 85.9
- Open weights
- No
Specification comparison
| Spec | GPT-5.1 Vision | Grok 3 Max | Edge |
|---|---|---|---|
| Input price / 1M | $17.76 | $17.66 | B |
| Output price / 1M | $80.59 | $89.12 | A |
| Context window | 400,000 | 2,000,000 | B |
| Max output | 16,384 | 32,768 | B |
| Average score | 84.8 | 85.9 | B |
| Arena Elo | 1462.4 | 1475.8 | B |
| Open weights | No | No | Tie |
Benchmark comparison
GPT-5.1 Vision wins 4, Grok 3 Max wins 7, and 1 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | GPT-5.1 Vision | Grok 3 Max | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 85.5 | 87.3 | 1.8 | Grok 3 Max |
| GPQA Diamond | 78.7 | 80.9 | 2.2 | Grok 3 Max |
| SWE-bench Verified | 73.6 | 73.6 | 0.0 | Tie |
| HumanEval | 89.6 | 91.9 | 2.3 | Grok 3 Max |
| MATH-500 | 89.1 | 91.9 | 2.8 | Grok 3 Max |
| AIME 2025 | 82.4 | 86.6 | 4.2 | Grok 3 Max |
| LiveCodeBench | 77.8 | 79.7 | 1.9 | Grok 3 Max |
| IFEval | 92.7 | 92.6 | 0.1 | GPT-5.1 Vision |
| TruthfulQA | 86.9 | 86.7 | 0.2 | GPT-5.1 Vision |
| HellaSwag | 92.1 | 91.8 | 0.3 | GPT-5.1 Vision |
| MMMU | 83.9 | 82.3 | 1.6 | GPT-5.1 Vision |
| Arena Elo | 1462.4 | 1475.8 | 13.4 | Grok 3 Max |
Price analysis
On a blended 3:1 input-to-output basis, GPT-5.1 Vision costs about $33.47 per million tokens and Grok 3 Max costs about $35.53. GPT-5.1 Vision is roughly 6% cheaper than Grok 3 Max. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.
Grok 3 Max has the larger context window at 2,000,000 tokens, compared with 400,000 for GPT-5.1 Vision. That matters for long documents, large codebases and multi-step agent traces.
Verdict
Across 12 shared benchmarks, GPT-5.1 Vision wins 4, Grok 3 Max wins 7, and 1 are tied. On the index average, Grok 3 Max leads GPT-5.1 Vision by 1.1 points (85.9 versus 84.8).
The price picture favours GPT-5.1 Vision. The context picture favours Grok 3 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 Grok 3 Max for quality-sensitive work and GPT-5.1 Vision for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.
Choose GPT-5.1 Vision if
- Unit cost matters and you want the cheaper blended price.
Choose Grok 3 Max if
- You want the higher average benchmark score in this index.
- You need the larger 2,000,000-token context window.
- You need the larger 32,768-token output limit.
FAQ
Is GPT-5.1 Vision better than Grok 3 Max?
On the index average, Grok 3 Max leads GPT-5.1 Vision by 1.1 points (85.9 versus 84.8). The better choice depends on price, context and your task. GPT-5.1 Vision wins 4 benchmarks, Grok 3 Max wins 7.
Which is cheaper, GPT-5.1 Vision or Grok 3 Max?
GPT-5.1 Vision is cheaper on a blended 3:1 basis at about $33.47 per million tokens, versus $35.53 for Grok 3 Max.
Which has the larger context window?
Grok 3 Max has the larger context window at 2,000,000 tokens. GPT-5.1 Vision has 400,000 tokens.
Are these models open weights?
GPT-5.1 Vision is proprietary; Grok 3 Max is proprietary.
Which should I choose for production?
If you need a single default, start with Grok 3 Max for quality-sensitive work and GPT-5.1 Vision for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.