Gemini 3.1 Pro vs GPT-6 Sol: pricing and benchmarks
Both charge $2.00 per 1M input tokens. GPT-6 Sol is 17% cheaper on output tokens ($10.00 vs $12.00 per 1M). On our document Q&A workload (50,000 questions a month), GPT-6 Sol costs $1,100 a month versus $1,160 for Gemini 3.1 Pro, 5% less. Epoch AI has not published a capability index score for GPT-6 Sol yet.
Prices verified September 26, 2026.
Which should you choose?
Epoch AI has not published a capability index score for GPT-6 Sol yet.
GPT-6 Sol costs $4.00 per 1M tokens (3:1 input-to-output mix) vs $4.50 for Gemini 3.1 Pro, 11% less.
Pricing and specs
| Gemini 3.1 Pro | GPT-6 Sol | |
|---|---|---|
| Provider | OpenAI | |
| API model ID | gemini-3.1-pro-preview | gpt-6-sol |
| Input / 1M tokens | $2.00 | $2.00 |
| Cached input / 1M tokens | $0.20 | $0.20 |
| Output / 1M tokens | $12.00 | $10.00 |
| Long-context rates | $4.00 in / $18.00 out above 200K prompt tokens | $4.00 in / $15.00 out on long-context requests |
| Context window | 1.05M tokens | 1.05M tokens |
| Max output | 66K tokens | 128K tokens |
| Batch discount | — | 50% off |
Benchmarks
| Gemini 3.1 Pro | GPT-6 Sol | |
|---|---|---|
| Epoch Capabilities Index | 155.0 | — |
| GPQA Diamond· Science reasoning | 92.6% | — |
| FrontierMath (Tiers 1–3)· Advanced math | 59.6% | — |
| SimpleQA Verified· Factual accuracy | 73.5% | — |
| ARC-AGI-2· Abstract reasoning | 77.1% | — |
| DeepSWE· Coding | 11.7% | — |
| APEX-Agents· Agentic work | 33.5% | — |
Source: Epoch AI, best recorded result per model (CC BY 4.0). A dash means no published score. See all benchmarks
Monthly cost for real workloads
| Workload | Gemini 3.1 Pro | GPT-6 Sol | Difference |
|---|---|---|---|
Support chatbot 100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each. | $780.00 | $700.00 | GPT-6 Sol 10% cheaper |
Document Q&A (RAG) 50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each. | $1,160 | $1,100 | GPT-6 Sol 5% cheaper |
Coding agent 10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens. | $536.00 | $496.00 | GPT-6 Sol 7% cheaper |
Estimates use standard list prices and ignore cache-write surcharges. Different tokenizers can count the same text differently, so test with your own prompts.
Gemini 3.1 Pro vs GPT-6 Sol cost calculator
- $1,100/mo$0.02 / request
- Gemini 3.1 ProGoogle$1,160/mo$0.02 / request
Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.
Gemini 3.1 Pro pricing notes
Google’s Gemini 3.1 Pro model, currently offered as a preview.
- Prompts over 200K tokens are billed at $4 input / $18 output per 1M tokens.
- No free tier on the Gemini API.
- Output price includes thinking tokens.
GPT-6 Sol pricing notes
OpenAI’s GPT-6 model built to power complex coding and agentic workflows.
- Cache writes are billed at $2.50 per 1M tokens.
- Fast mode costs 2x the standard rate; Flex costs half.
- Regional (data residency) endpoints add a 10% uplift, and EU data residency is available only with standard processing.
Frequently asked questions
- Is Gemini 3.1 Pro cheaper than GPT-6 Sol?
- Both charge $2.00 per 1M input tokens. GPT-6 Sol is 17% cheaper on output tokens ($10.00 vs $12.00 per 1M). On our document Q&A workload (50,000 questions a month), GPT-6 Sol costs $1,100 a month versus $1,160 for Gemini 3.1 Pro, 5% less.
- Which is more capable, Gemini 3.1 Pro or GPT-6 Sol?
- Epoch AI has not published a capability index score for GPT-6 Sol yet.
- How much does Gemini 3.1 Pro cost per 1M tokens?
- Gemini 3.1 Pro costs $2.00 per 1M input tokens and $12.00 per 1M output tokens, and $0.20 per 1M cached input tokens on Google’s standard tier.
- How much does GPT-6 Sol cost per 1M tokens?
- GPT-6 Sol costs $2.00 per 1M input tokens and $10.00 per 1M output tokens, and $0.20 per 1M cached input tokens on OpenAI’s standard tier.
- Which has the larger context window, Gemini 3.1 Pro or GPT-6 Sol?
- GPT-6 Sol has the larger context window: 1.05M tokens versus 1.05M for Gemini 3.1 Pro.