Grok 4 vs o3 Max: which model should you choose?
We compared Grok 4 and o3 Max on price, context window and 12 benchmarks. Grok 4 has the stronger average benchmark score; Grok 4 is cheaper on a blended 3:1 basis.
Grok 4
Grok 4 is a frontier model from xAI. It offers a 200,000-token context window, costs $17.90 per million input tokens and $84.75 per million output tokens, and averages 86.5 across the index's benchmark suite.
- Input
- $17.90 / 1M
- Output
- $84.75 / 1M
- Context
- 200,000
- Avg score
- 86.5
- 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 | Grok 4 | o3 Max | Edge |
|---|---|---|---|
| Input price / 1M | $17.90 | $17.82 | B |
| Output price / 1M | $84.75 | $90.55 | A |
| Context window | 200,000 | 2,000,000 | B |
| Max output | 32,768 | 128,000 | B |
| Average score | 86.5 | 84.8 | A |
| Arena Elo | 1457.8 | 1465.2 | B |
| Open weights | No | No | Tie |
Benchmark comparison
Grok 4 wins 8, o3 Max wins 4, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | Grok 4 | o3 Max | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 87.8 | 84.9 | 2.9 | Grok 4 |
| GPQA Diamond | 82.6 | 82.7 | 0.1 | o3 Max |
| SWE-bench Verified | 77.9 | 71.8 | 6.1 | Grok 4 |
| HumanEval | 92.0 | 89.8 | 2.2 | Grok 4 |
| MATH-500 | 90.8 | 87.0 | 3.8 | Grok 4 |
| AIME 2025 | 82.2 | 86.2 | 4.0 | o3 Max |
| LiveCodeBench | 82.2 | 76.4 | 5.8 | Grok 4 |
| IFEval | 91.6 | 92.5 | 0.9 | o3 Max |
| TruthfulQA | 87.6 | 87.3 | 0.3 | Grok 4 |
| HellaSwag | 93.9 | 93.4 | 0.5 | Grok 4 |
| MMMU | 82.9 | 80.8 | 2.1 | Grok 4 |
| Arena Elo | 1457.8 | 1465.2 | 7.4 | o3 Max |
Price analysis
On a blended 3:1 input-to-output basis, Grok 4 costs about $34.61 per million tokens and o3 Max costs about $36.00. Grok 4 is roughly 4% 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 Grok 4. That matters for long documents, large codebases and multi-step agent traces.
Verdict
Across 12 shared benchmarks, Grok 4 wins 8, o3 Max wins 4, and 0 are tied. On the index average, Grok 4 leads o3 Max by 1.7 points (86.5 versus 84.8).
The price picture favours Grok 4. 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 Grok 4 for quality-sensitive work, and check whether its price holds at your expected volume before committing.
Choose Grok 4 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 Grok 4 better than o3 Max?
On the index average, Grok 4 leads o3 Max by 1.7 points (86.5 versus 84.8). The better choice depends on price, context and your task. Grok 4 wins 8 benchmarks, o3 Max wins 4.
Which is cheaper, Grok 4 or o3 Max?
Grok 4 is cheaper on a blended 3:1 basis at about $34.61 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. Grok 4 has 200,000 tokens.
Are these models open weights?
Grok 4 is proprietary; o3 Max is proprietary.
Which should I choose for production?
If you need a single default, start with Grok 4 for quality-sensitive work, and check whether its price holds at your expected volume before committing.