Gemini 3 Flash Reasoning vs GPT-4.1 Reasoning: which model should you choose?
We compared Gemini 3 Flash Reasoning and GPT-4.1 Reasoning on price, context window and 12 benchmarks. GPT-4.1 Reasoning has the stronger average benchmark score; Gemini 3 Flash Reasoning is cheaper on a blended 3:1 basis.
Gemini 3 Flash Reasoning
Gemini 3 Flash Reasoning is a frontier model from Google DeepMind. It offers a 128,000-token context window, costs $17.05 per million input tokens and $66.77 per million output tokens, and averages 83.7 across the index's benchmark suite.
- Input
- $17.05 / 1M
- Output
- $66.77 / 1M
- Context
- 128,000
- Avg score
- 83.7
- Open weights
- No
GPT-4.1 Reasoning
GPT-4.1 Reasoning is a frontier model from OpenAI. It offers a 1,000,000-token context window, costs $16.97 per million input tokens and $82.05 per million output tokens, and averages 83.8 across the index's benchmark suite.
- Input
- $16.97 / 1M
- Output
- $82.05 / 1M
- Context
- 1,000,000
- Avg score
- 83.8
- Open weights
- No
Specification comparison
| Spec | Gemini 3 Flash Reasoning | GPT-4.1 Reasoning | Edge |
|---|---|---|---|
| Input price / 1M | $17.05 | $16.97 | B |
| Output price / 1M | $66.77 | $82.05 | A |
| Context window | 128,000 | 1,000,000 | B |
| Max output | 32,768 | 4,096 | A |
| Average score | 83.7 | 83.8 | B |
| Arena Elo | 1446.9 | 1466.7 | B |
| Open weights | No | No | Tie |
Benchmark comparison
Gemini 3 Flash Reasoning wins 4, GPT-4.1 Reasoning wins 8, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.
| Benchmark | Gemini 3 Flash Reasoning | GPT-4.1 Reasoning | Gap | Winner |
|---|---|---|---|---|
| MMLU-Pro | 87.2 | 87.3 | 0.1 | GPT-4.1 Reasoning |
| GPQA Diamond | 81.8 | 77.8 | 4.0 | Gemini 3 Flash Reasoning |
| SWE-bench Verified | 72.5 | 73.1 | 0.6 | GPT-4.1 Reasoning |
| HumanEval | 86.9 | 88.8 | 1.9 | GPT-4.1 Reasoning |
| MATH-500 | 86.2 | 89.1 | 2.9 | GPT-4.1 Reasoning |
| AIME 2025 | 79.4 | 82.1 | 2.7 | GPT-4.1 Reasoning |
| LiveCodeBench | 77.7 | 80.5 | 2.8 | GPT-4.1 Reasoning |
| IFEval | 90.2 | 91.6 | 1.4 | GPT-4.1 Reasoning |
| TruthfulQA | 86.6 | 84.3 | 2.3 | Gemini 3 Flash Reasoning |
| HellaSwag | 92.2 | 89.4 | 2.8 | Gemini 3 Flash Reasoning |
| MMMU | 79.8 | 77.5 | 2.3 | Gemini 3 Flash Reasoning |
| Arena Elo | 1446.9 | 1466.7 | 19.8 | GPT-4.1 Reasoning |
Price analysis
On a blended 3:1 input-to-output basis, Gemini 3 Flash Reasoning costs about $29.48 per million tokens and GPT-4.1 Reasoning costs about $33.24. Gemini 3 Flash Reasoning is roughly 11% cheaper than GPT-4.1 Reasoning. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.
GPT-4.1 Reasoning has the larger context window at 1,000,000 tokens, compared with 128,000 for Gemini 3 Flash Reasoning. That matters for long documents, large codebases and multi-step agent traces.
Verdict
Across 12 shared benchmarks, Gemini 3 Flash Reasoning wins 4, GPT-4.1 Reasoning wins 8, and 0 are tied. On the index average, GPT-4.1 Reasoning leads Gemini 3 Flash Reasoning by 0.1 points (83.8 versus 83.7).
The price picture favours Gemini 3 Flash Reasoning. The context picture favours GPT-4.1 Reasoning. 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 GPT-4.1 Reasoning for quality-sensitive work and Gemini 3 Flash Reasoning for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.
Choose Gemini 3 Flash Reasoning if
- Unit cost matters and you want the cheaper blended price.
- You need the larger 32,768-token output limit.
Choose GPT-4.1 Reasoning if
- You want the higher average benchmark score in this index.
- You need the larger 1,000,000-token context window.
FAQ
Is Gemini 3 Flash Reasoning better than GPT-4.1 Reasoning?
On the index average, GPT-4.1 Reasoning leads Gemini 3 Flash Reasoning by 0.1 points (83.8 versus 83.7). The better choice depends on price, context and your task. Gemini 3 Flash Reasoning wins 4 benchmarks, GPT-4.1 Reasoning wins 8.
Which is cheaper, Gemini 3 Flash Reasoning or GPT-4.1 Reasoning?
Gemini 3 Flash Reasoning is cheaper on a blended 3:1 basis at about $29.48 per million tokens, versus $33.24 for GPT-4.1 Reasoning.
Which has the larger context window?
GPT-4.1 Reasoning has the larger context window at 1,000,000 tokens. Gemini 3 Flash Reasoning has 128,000 tokens.
Are these models open weights?
Gemini 3 Flash Reasoning is proprietary; GPT-4.1 Reasoning is proprietary.
Which should I choose for production?
If you need a single default, start with GPT-4.1 Reasoning for quality-sensitive work and Gemini 3 Flash Reasoning for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.