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Gemini 2.5 Pro vs Gemini 3 Pro

Gemini 2.5 Pro (2025) and Gemini 3 Pro (2025) are general-purpose language models from Google DeepMind. Gemini 2.5 Pro ships a 1M-token context window, while Gemini 3 Pro ships a 1M-token context window. On MMLU PRO, Gemini 3 Pro leads by 3.9 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 Pro for general evaluation; Gemini 2.5 Pro is better when coding workflow support matters more.

Decision scorecard

Local evidence first
SignalGemini 2.5 ProGemini 3 Pro
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window1M1M
Cheapest output$10/1M tokens$5/1M tokens
Provider routes3 tracked2 tracked
Shared benchmarks2 rowsMMLU PRO leader

Decision tradeoffs

Choose Gemini 2.5 Pro when...
  • Gemini 2.5 Pro has broader tracked provider coverage for fallback and procurement flexibility.
  • Gemini 2.5 Pro uniquely exposes Structured outputs in local model data.
  • Local decision data tags Gemini 2.5 Pro for Coding, RAG, and Agents.
Choose Gemini 3 Pro when...
  • Gemini 3 Pro leads the largest shared benchmark signal on MMLU PRO by 3.9 points.
  • Gemini 3 Pro has the lower cheapest tracked output price at $5/1M tokens.
  • Local decision data tags Gemini 3 Pro for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output prices on this page.

Lower estimate Gemini 3 Pro

Gemini 2.5 Pro

$3,500

Cheapest tracked route: Google AI Studio

Gemini 3 Pro

$2,250

Cheapest tracked route: GCP Vertex AI

Estimated monthly gap: $1,250. Batch, cache, and negotiated pricing are excluded from this local estimate.

Switch friction

Gemini 2.5 Pro -> Gemini 3 Pro
Local recipe
  • Provider overlap exists on GCP Vertex AI; start route-level A/B tests there.
  • Gemini 3 Pro is $5/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Structured outputs before moving production traffic.
  • Use this scaffold for Gemini users checking whether Gemini 3 Pro changes the answer for long-context, RAG, or tool-use workloads.
  • Start from context-window fit, then compare output-token pricing and cache availability.
  • Preserve Gemini 2.5 Pro as a candidate when the page lacks sourced peer benchmarks for the task.
Review migration path
Gemini 3 Pro -> Gemini 2.5 Pro
  • Provider overlap exists on GCP Vertex AI; start route-level A/B tests there.
  • Gemini 2.5 Pro is $5/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Gemini 2.5 Pro adds Structured outputs in local capability data.

Specs

Specification
Released2025-06-172025-12-11
Context window1M1M
Parameters
Architecturedecoder onlydecoder only
LicenseProprietaryProprietary
Knowledge cutoff2025-012025-01

Pricing and availability

Pricing attributeGemini 2.5 ProGemini 3 Pro
Input price$1.25/1M tokens$1.25/1M tokens
Output price$10/1M tokens$5/1M tokens
Providers

Capabilities

CapabilityGemini 2.5 ProGemini 3 Pro
VisionYesYes
MultimodalYesYes
ReasoningNoNo
Function callingYesYes
Tool useYesYes
Structured outputsYesNo
Code executionYesYes

Benchmarks

BenchmarkGemini 2.5 ProGemini 3 Pro
MMLU PRO86.290.1
Chatbot Arena1398.01486.0

Deep dive

On shared benchmark coverage, MMLU PRO has Gemini 2.5 Pro at 86.2 and Gemini 3 Pro at 90.1, with Gemini 3 Pro ahead by 3.9 points; Chatbot Arena has Gemini 2.5 Pro at 1398 and Gemini 3 Pro at 1486, with Gemini 3 Pro ahead by 88 points. The largest visible gap is 88 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 Pro lists $1.25/1M input and $5/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemini 3 Pro lower by about $1.5 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 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 Pro?

Gemini 2.5 Pro supports 1M tokens, while Gemini 3 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 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 Pro costs $1.25/1M input and $5/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Gemini 2.5 Pro or Gemini 3 Pro open source?

Gemini 2.5 Pro is listed under Proprietary. Gemini 3 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 Pro?

Both Gemini 2.5 Pro and Gemini 3 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 Pro?

Both Gemini 2.5 Pro and Gemini 3 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 Pro?

Gemini 2.5 Pro is available on Google AI Studio, GCP Vertex AI, and OpenRouter. Gemini 3 Pro is available on Replicate API and GCP Vertex AI. 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.