Gemini 2.5 Pro vs Gemini 3.1 Pro
Gemini 2.5 Pro (2025) and Gemini 3.1 Pro (2026) are general-purpose language models from Google DeepMind. Gemini 2.5 Pro ships a 1M-token context window, while Gemini 3.1 Pro ships a 1M-token context window. On SWE-bench Verified, Gemini 3.1 Pro leads by 17.4 pts. On pricing, Gemini 2.5 Pro costs $1.25/1M input tokens versus $1.25/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.
Pick Gemini 3.1 Pro for coding; Gemini 2.5 Pro is better when coding workflow support matters more.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-06-17 | 2026-02-19 |
| Context window | 1M | 1M |
| Parameters | — | — |
| Architecture | decoder only | decoder only |
| License | Proprietary | Proprietary |
| Knowledge cutoff | 2025-01 | 2025-01 |
Pricing and availability
| Pricing attribute | Gemini 2.5 Pro | Gemini 3.1 Pro |
|---|---|---|
| Input price | $1.25/1M tokens | $1.25/1M tokens |
| Output price | $10/1M tokens | $10/1M tokens |
| Providers |
Capabilities
| Capability | Gemini 2.5 Pro | Gemini 3.1 Pro |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | No | No |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | No |
| Code execution | Yes | Yes |
Benchmarks
| Benchmark | Gemini 2.5 Pro | Gemini 3.1 Pro |
|---|---|---|
| SWE-bench Verified | 63.2 | 80.6 |
| Google-Proof Q&A | 86.4 | 94.3 |
| Chatbot Arena | 1398.0 | 1493.0 |
Deep dive
On shared benchmark coverage, SWE-bench Verified has Gemini 2.5 Pro at 63.2 and Gemini 3.1 Pro at 80.6, with Gemini 3.1 Pro ahead by 17.4 points; Google-Proof Q&A has Gemini 2.5 Pro at 86.4 and Gemini 3.1 Pro at 94.3, with Gemini 3.1 Pro ahead by 7.9 points; Chatbot Arena has Gemini 2.5 Pro at 1398 and Gemini 3.1 Pro at 1493, with Gemini 3.1 Pro ahead by 95 points. The largest visible gap is 95 points on Chatbot Arena, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on structured outputs: Gemini 2.5 Pro. Both models share vision, multimodal input, function calling, and tool use, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, Gemini 2.5 Pro lists $1.25/1M input and $10/1M output tokens, while Gemini 3.1 Pro lists $1.25/1M input and $10/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemini 2.5 Pro lower by about $0 per million blended tokens. Availability is 3 providers versus 2, so concentration risk also matters.
Choose Gemini 2.5 Pro when coding workflow support and broader provider choice are central to the workload. Choose Gemini 3.1 Pro when coding workflow support are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, Gemini 2.5 Pro or Gemini 3.1 Pro?
Gemini 2.5 Pro supports 1M tokens, while Gemini 3.1 Pro supports 1M tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, Gemini 2.5 Pro or Gemini 3.1 Pro?
Gemini 2.5 Pro is cheaper on tracked token pricing. Gemini 2.5 Pro costs $1.25/1M input and $10/1M output tokens. Gemini 3.1 Pro costs $1.25/1M input and $10/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Gemini 2.5 Pro or Gemini 3.1 Pro open source?
Gemini 2.5 Pro is listed under Proprietary. Gemini 3.1 Pro is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, Gemini 2.5 Pro or Gemini 3.1 Pro?
Both Gemini 2.5 Pro and Gemini 3.1 Pro expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Which is better for multimodal input, Gemini 2.5 Pro or Gemini 3.1 Pro?
Both Gemini 2.5 Pro and Gemini 3.1 Pro expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Where can I run Gemini 2.5 Pro and Gemini 3.1 Pro?
Gemini 2.5 Pro is available on Google AI Studio, GCP Vertex AI, and OpenRouter. Gemini 3.1 Pro is available on Google AI Studio and Replicate API. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-11. Data sourced from public model cards and provider documentation.