Gemini 2.5 Pro vs GPT-5.1
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Gemini 2.5 Pro
70.9Google · Mar 2025
Google's 2025 workhorse flagship — first mainstream thinking model with a 1M context, still widely deployed.
GPT-5.1
59.6OpenAI · Nov 2025
A November 2025 update to GPT-5 with adaptive reasoning that spends thinking tokens only when a task needs them.
The verdict
GPT-5.1 wins 3 of the 3 benchmarks these models share, against 0 for Gemini 2.5 Pro. Gemini 2.5 Pro also takes 1.0M of context versus 400K for GPT-5.1.
Benchmark head-to-head 0–3
Specs & pricing
| Gemini 2.5 Pro | GPT-5.1 | |
|---|---|---|
| modhub Index | 70.9 | 59.6 |
| Input price / 1M | $1.25 | $1.25 |
| Output price / 1M | $10 | $10 |
| Context window | 1.0M | 400K |
| Max output | 66K | 128K |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image, audio, video | text, image |
| Knowledge cutoff | Jan 2025 | Sep 2024 |
| Released | Mar 2025 | Nov 2025 |
| Example monthly cost* | $27.50 | $27.50 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Gemini 2.5 Pro or GPT-5.1?
- GPT-5.1 wins 3 of the 3 benchmarks these models share, against 0 for Gemini 2.5 Pro. Gemini 2.5 Pro also takes 1.0M of context versus 400K for GPT-5.1.
- Which is cheaper, Gemini 2.5 Pro or GPT-5.1?
- Gemini 2.5 Pro costs $1.25/$10 per million input/output tokens, while GPT-5.1 costs $1.25/$10. For a typical workload of 10M input and 1.5M output tokens per month, that's $27.50 versus $27.50.
- Which model is better for coding, Gemini 2.5 Pro or GPT-5.1?
- On SWE-bench Verified — the standard agentic-coding benchmark — GPT-5.1 scores 76.3% versus 63.8% for Gemini 2.5 Pro, making GPT-5.1 the stronger pick for coding agents.