High-volume, cost-sensitive work
Choose GPT-4o
GPT-4o costs 3% less on a typical mix of three input tokens for every output token ($4.38 against $4.50 per million tokens).
Gemini 3.1 Pro vs GPT-4o: price, context and capabilities
Choose Gemini 3.1 Pro for reused prompts and documents (RAG, agents), very long inputs, agentic coding, tool use and support agents, reasoning over long documents and the latest release. Choose GPT-4o for high-volume, cost-sensitive work and writing and code generation.
In short
- GPT-4o is 3% cheaper than Gemini 3.1 Pro at the headline price ($4.38 / 1M tokens vs $4.50 / 1M tokens).
- Gemini 3.1 Pro reads more per request: 1.05M tokens against 128k.
- Gemini 3.1 Pro is the newer model (February 2026, against May 13, 2024).
- Only Gemini 3.1 Pro offers reasoning.
Which should you choose?
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Writing and code generation
Choose GPT-4o
GPT-4o charges $10.00 per million output tokens, against $12.00 for Gemini 3.1 Pro. Output dominates the bill when answers are long.
Reused prompts and documents (RAG, agents)
Choose Gemini 3.1 Pro
Gemini 3.1 Pro charges $0.20 per million cached input tokens, against $1.25 for GPT-4o.
Very long inputs
Choose Gemini 3.1 Pro
Gemini 3.1 Pro reads up to 1.05M tokens per request, against 128k for GPT-4o.
Agentic coding
Choose Gemini 3.1 Pro
Gemini 3.1 Pro scores 53.8% on Terminal-Bench Hard, against 8.3% for GPT-4o.
Tool use and support agents
Choose Gemini 3.1 Pro
Gemini 3.1 Pro scores 95.6% on τ²-Bench (agentic tool use), against 25.1% for GPT-4o.
Reasoning over long documents
Choose Gemini 3.1 Pro
Gemini 3.1 Pro scores 82% on Long-context reasoning (AA-LCR), against 49.3% for GPT-4o.
Latest release
Choose Gemini 3.1 Pro
Gemini 3.1 Pro is the newer release (February 2026, against May 13, 2024 for GPT-4o).
Monthly cost at three volumes
| Volume | Gemini 3.1 Pro | GPT-4o | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $5.00 | $5.00 | = |
| Production: 20M input, 5M output tokens | $100.00 | $100.00 | = |
| Scale: 500M input, 100M output tokens | $2,200 | $2,250 | Gemini 3.1 Pro, $50.00 less |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| Gemini 3.1 Pro | GPT-4o | |
|---|---|---|
| Provider | OpenAI | |
| Category | Language models | Language models |
| Status | Preview | Deprecated |
| Headline price | $4.50 / 1M tokens | $4.38 / 1M tokens |
| Input | $2.00 / 1M tokens | $2.50 / 1M tokens |
| Output | $12.00 / 1M tokens | $10.00 / 1M tokens |
| Cached input | $0.20 / 1M tokens | $1.25 / 1M tokens |
| Context window | 1.05M | 128k |
| Max output | 66k | 16k |
| Released | February 2026 | May 13, 2024 |
| Knowledge cutoff | No data | October 2023 |
| Licence | Proprietary | Proprietary |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API | Vision, Tool calling, Structured output, Prompt caching, Batch API |
| API model id | gemini-3.1-pro-preview | gpt-4o |
Benchmarks side by side
Leader in bold.
| Benchmark | Gemini 3.1 Pro | GPT-4o |
|---|---|---|
| Terminal-Bench Hard | 53.8% | 8.3% |
| GPQA Diamond | 94.1% | 54.3% |
| Humanity's Last Exam | 47% | 2.4% |
| IFBench (instruction following) | 77.1% | 34.3% |
| τ²-Bench (agentic tool use) | 95.6% | 25.1% |
| Long-context reasoning (AA-LCR) | 82% | 49.3% |
| Intelligence Index | 29.7 | No data |
| SciCode | 58.7% | No data |
| MMMU-Pro (visual reasoning) | 82.4% | No data |
Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.
Frequently asked questions
Should I choose Gemini 3.1 Pro or GPT-4o?
Choose Gemini 3.1 Pro for reused prompts and documents (RAG, agents), very long inputs, agentic coding, tool use and support agents, reasoning over long documents and the latest release. Choose GPT-4o for high-volume, cost-sensitive work and writing and code generation.
Which is cheaper, Gemini 3.1 Pro or GPT-4o?
GPT-4o is 3% cheaper than Gemini 3.1 Pro at the headline price ($4.38 / 1M tokens vs $4.50 / 1M tokens).
Which has the larger context window, Gemini 3.1 Pro or GPT-4o?
Gemini 3.1 Pro reads more per request: 1.05M tokens against 128k.
What is the difference between Gemini 3.1 Pro and GPT-4o?
Gemini 3.1 Pro is made by Google and GPT-4o by OpenAI. GPT-4o is 3% cheaper than Gemini 3.1 Pro at the headline price ($4.38 / 1M tokens vs $4.50 / 1M tokens). Gemini 3.1 Pro reads more per request: 1.05M tokens against 128k. Gemini 3.1 Pro is the newer model (February 2026, against May 13, 2024). Only Gemini 3.1 Pro offers reasoning.
Which is better for coding, Gemini 3.1 Pro or GPT-4o?
Gemini 3.1 Pro scores 53.8% on Terminal-Bench Hard, against 8.3% for GPT-4o.
How much do Gemini 3.1 Pro and GPT-4o cost per month?
At 20 million input and 5 million output tokens a month, Gemini 3.1 Pro costs $100.00 and GPT-4o costs $100.00, at standard rates.
Which is newer, Gemini 3.1 Pro or GPT-4o?
Gemini 3.1 Pro was released on February 2026 and GPT-4o on May 13, 2024.