Gemini 2.5 Flash vs Nano Banana 2 (Gemini 3.1 Flash Image)
Gemini 2.5 Flash (2025) and Nano Banana 2 (Gemini 3.1 Flash Image) (2026) are frontier reasoning models from Google DeepMind. Gemini 2.5 Flash ships a 1m-token context window, while Nano Banana 2 (Gemini 3.1 Flash Image) ships a 131k-token context window. On pricing, Gemini 2.5 Flash costs $0.30/1M input tokens versus $0.50/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Gemini 2.5 Flash is ~67% cheaper at $0.30/1M; pay for Nano Banana 2 (Gemini 3.1 Flash Image) only for reasoning depth.
Decision scorecard
Local evidence first| Signal | Gemini 2.5 Flash | Nano Banana 2 (Gemini 3.1 Flash Image) |
|---|---|---|
| Best for | multimodal apps, tool-calling agents, and long-context analysis | reasoning-heavy apps and multimodal apps |
| Decision fit | Coding, RAG, and Agents | Long context and Vision |
| Context window | 1m | 131k |
| Cheapest output | $2.50/1M tokens | $60/1M tokens |
| Provider routes | 5 tracked | 1 tracked |
| Shared benchmarks | 0 shared | 0 shared |
Decision tradeoffs
- Gemini 2.5 Flash has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Gemini 2.5 Flash has the lower cheapest tracked output price at $2.50/1M tokens.
- Gemini 2.5 Flash has broader tracked provider coverage for fallback and procurement flexibility.
- Gemini 2.5 Flash uniquely exposes Function calling, Tool use, and Structured outputs in local model data.
- Local decision data tags Gemini 2.5 Flash for Coding, RAG, and Agents.
- Nano Banana 2 (Gemini 3.1 Flash Image) uniquely exposes Reasoning in local model data.
- Local decision data tags Nano Banana 2 (Gemini 3.1 Flash Image) for Long context and Vision.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Gemini 2.5 Flash
$865
Cheapest tracked route/tier: Google AI Studio
Nano Banana 2 (Gemini 3.1 Flash Image)
$15,400
Cheapest tracked route/tier: Google AI Studio
Estimated monthly gap: $14,535. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on Google AI Studio; start route-level A/B tests there.
- Nano Banana 2 (Gemini 3.1 Flash Image) is $57.50/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Function calling, Tool use, and Structured outputs before moving production traffic.
- Nano Banana 2 (Gemini 3.1 Flash Image) adds Reasoning in local capability data.
- Provider overlap exists on Google AI Studio; start route-level A/B tests there.
- Gemini 2.5 Flash is $57.50/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Reasoning before moving production traffic.
- Gemini 2.5 Flash adds Function calling, Tool use, and Structured outputs in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-06-17 | 2026-05-28 |
| Context window | 1m | 131k |
| Parameters | — | — |
| Architecture | Decoder Only | Decoder Only |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Commercial use | Commercial use: conditional | Commercial use: conditional |
| Knowledge cutoff | 2025-01 | 2025-01 |
Pricing and availability
| Pricing attribute | Gemini 2.5 Flash | Nano Banana 2 (Gemini 3.1 Flash Image) |
|---|---|---|
| Input price | $0.30/1M tokens | $0.50/1M tokens |
| Output price | $2.50/1M tokens | $60/1M tokens |
| Providers |
Capabilities
| Capability | Gemini 2.5 Flash | Nano Banana 2 (Gemini 3.1 Flash Image) |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | No | Yes |
| Function calling | Yes | No |
| Tool use | Yes | No |
| Structured outputs | Yes | No |
| Code execution | Yes | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark scores are currently available for this pair.
Deep dive
The capability footprint differs most on reasoning mode: Nano Banana 2 (Gemini 3.1 Flash Image), function calling: Gemini 2.5 Flash, tool use: Gemini 2.5 Flash, structured outputs: Gemini 2.5 Flash, and code execution: Gemini 2.5 Flash. Both models share vision and multimodal input, 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 Flash lists $0.30/1M input and $2.50/1M output tokens on the cheapest tracked provider, while Nano Banana 2 (Gemini 3.1 Flash Image) lists $0.50/1M input and $60/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemini 2.5 Flash lower by about $17.39 per million blended tokens. Availability is 5 providers versus 1, so concentration risk also matters.
Choose Gemini 2.5 Flash when coding workflow support, larger context windows, and lower input-token cost are central to the workload. Choose Nano Banana 2 (Gemini 3.1 Flash Image) when reasoning depth 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 Flash or Nano Banana 2 (Gemini 3.1 Flash Image)?
Gemini 2.5 Flash supports 1m tokens, while Nano Banana 2 (Gemini 3.1 Flash Image) supports 131k 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 Flash or Nano Banana 2 (Gemini 3.1 Flash Image)?
Gemini 2.5 Flash is cheaper on tracked token pricing. Gemini 2.5 Flash costs $0.30/1M input and $2.50/1M output tokens. Nano Banana 2 (Gemini 3.1 Flash Image) costs $0.50/1M input and $60/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Gemini 2.5 Flash or Nano Banana 2 (Gemini 3.1 Flash Image) open source?
Gemini 2.5 Flash is listed under Proprietary. Nano Banana 2 (Gemini 3.1 Flash Image) 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 Flash or Nano Banana 2 (Gemini 3.1 Flash Image)?
Both Gemini 2.5 Flash and Nano Banana 2 (Gemini 3.1 Flash Image) 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 Flash or Nano Banana 2 (Gemini 3.1 Flash Image)?
Both Gemini 2.5 Flash and Nano Banana 2 (Gemini 3.1 Flash Image) 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 Flash and Nano Banana 2 (Gemini 3.1 Flash Image)?
Gemini 2.5 Flash is available on Google AI Studio, GCP Vertex AI, Replicate API, OpenRouter, and Vercel AI Gateway. Nano Banana 2 (Gemini 3.1 Flash Image) is available on Google AI Studio. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
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Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.