High-volume, cost-sensitive work
Choose Gemini 2.5 Pro
Gemini 2.5 Pro costs 14% less on a typical mix of three input tokens for every output token ($3.44 against $4.00 per million tokens).
Gemini 2.5 Pro vs GPT-6.1 Sol: price, context and capabilities
Choose Gemini 2.5 Pro for high-volume, cost-sensitive work. Choose GPT-6.1 Sol for reused prompts and documents (RAG, agents), the hardest reasoning tasks, reasoning over long documents, the latest release and the most recent knowledge.
In short
- Gemini 2.5 Pro is 14% cheaper than GPT-6.1 Sol at the headline price ($3.44 / 1M tokens vs $4.00 / 1M tokens).
- GPT-6.1 Sol reads more per request: 1.05M tokens against 1.05M.
- GPT-6.1 Sol is the newer model (Sep 29, 2026, against June 2025).
Which should you choose?
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Reused prompts and documents (RAG, agents)
Choose GPT-6.1 Sol
GPT-6.1 Sol charges $0.10 per million cached input tokens, against $0.13 for Gemini 2.5 Pro.
Hardest reasoning tasks
Choose GPT-6.1 Sol
GPT-6.1 Sol scores 51.8 on the Artificial Analysis Intelligence Index, against 16.1 for Gemini 2.5 Pro.
Reasoning over long documents
Choose GPT-6.1 Sol
GPT-6.1 Sol scores 83% on Long-context reasoning (AA-LCR), against 69% for Gemini 2.5 Pro.
Latest release
Choose GPT-6.1 Sol
GPT-6.1 Sol is the newer release (Sep 29, 2026, against June 2025 for Gemini 2.5 Pro).
Most recent knowledge
Choose GPT-6.1 Sol
GPT-6.1 Sol was trained on data up to April 2026, against January 2025 for Gemini 2.5 Pro.
Monthly cost at three volumes
| Volume | Gemini 2.5 Pro | GPT-6.1 Sol | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $3.75 | $4.50 | Gemini 2.5 Pro, $0.75 less |
| Production: 20M input, 5M output tokens | $75.00 | $90.00 | Gemini 2.5 Pro, $15.00 less |
| Scale: 500M input, 100M output tokens | $1,625 | $2,000 | Gemini 2.5 Pro, $375.00 less |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| Gemini 2.5 Pro | GPT-6.1 Sol | |
|---|---|---|
| Provider | OpenAI | |
| Category | Language models | Language models |
| Status | Legacy | Generally available |
| Headline price | $3.44 / 1M tokens | $4.00 / 1M tokens |
| Input | $1.25 / 1M tokens | $2.00 / 1M tokens |
| Output | $10.00 / 1M tokens | $10.00 / 1M tokens |
| Cached input | $0.125 / 1M tokens | $0.10 / 1M tokens |
| Context window | 1.05M | 1.05M |
| Max output | 66k | 128k |
| Released | June 2025 | Sep 29, 2026 |
| Knowledge cutoff | January 2025 | April 2026 |
| Licence | Proprietary | Proprietary |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API |
| API model id | gemini-2.5-pro | gpt-6.1-sol |
Benchmarks side by side
Leader in bold.
| Benchmark | Gemini 2.5 Pro | GPT-6.1 Sol |
|---|---|---|
| Intelligence Index | 16.1 | 51.8 |
| SciCode | 46.3% | 54.2% |
| Humanity's Last Exam | 22.5% | 52.9% |
| MMMU-Pro (visual reasoning) | 74.9% | 86% |
| Long-context reasoning (AA-LCR) | 69% | 83% |
| Terminal-Bench Hard | 26.5% | No data |
| GPQA Diamond | 84.4% | No data |
| IFBench (instruction following) | 48.7% | No data |
| τ²-Bench (agentic tool use) | 54.1% | 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 2.5 Pro or GPT-6.1 Sol?
Choose Gemini 2.5 Pro for high-volume, cost-sensitive work. Choose GPT-6.1 Sol for reused prompts and documents (RAG, agents), the hardest reasoning tasks, reasoning over long documents, the latest release and the most recent knowledge.
Which is cheaper, Gemini 2.5 Pro or GPT-6.1 Sol?
Gemini 2.5 Pro is 14% cheaper than GPT-6.1 Sol at the headline price ($3.44 / 1M tokens vs $4.00 / 1M tokens).
Which has the larger context window, Gemini 2.5 Pro or GPT-6.1 Sol?
GPT-6.1 Sol reads more per request: 1.05M tokens against 1.05M.
What is the difference between Gemini 2.5 Pro and GPT-6.1 Sol?
Gemini 2.5 Pro is made by Google and GPT-6.1 Sol by OpenAI. Gemini 2.5 Pro is 14% cheaper than GPT-6.1 Sol at the headline price ($3.44 / 1M tokens vs $4.00 / 1M tokens). GPT-6.1 Sol reads more per request: 1.05M tokens against 1.05M. GPT-6.1 Sol is the newer model (Sep 29, 2026, against June 2025).
How much do Gemini 2.5 Pro and GPT-6.1 Sol cost per month?
At 20 million input and 5 million output tokens a month, Gemini 2.5 Pro costs $75.00 and GPT-6.1 Sol costs $90.00, at standard rates.
Which is newer, Gemini 2.5 Pro or GPT-6.1 Sol?
GPT-6.1 Sol was released on Sep 29, 2026 and Gemini 2.5 Pro on June 2025.