Nano Banana 2 (Gemini 3.1 Flash Image) vs o3-pro
Nano Banana 2 (Gemini 3.1 Flash Image) (2026) and o3-pro (2025) are frontier-tier reasoning models from Google DeepMind and OpenAI. Nano Banana 2 (Gemini 3.1 Flash Image) ships a 131k-token context window, while o3-pro ships a 200k-token context window. On pricing, Nano Banana 2 (Gemini 3.1 Flash Image) costs $0.50/1M input tokens versus $20/1M 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.
Nano Banana 2 (Gemini 3.1 Flash Image) is ~3900% cheaper at $0.50/1M; pay for o3-pro only for coding workflow support.
Decision scorecard
Local evidence first| Signal | Nano Banana 2 (Gemini 3.1 Flash Image) | o3-pro |
|---|---|---|
| Best for | reasoning-heavy apps and multimodal apps | reasoning-heavy apps, multimodal apps, and tool-calling agents |
| Decision fit | Long context and Vision | Coding, RAG, and Agents |
| Context window | 131k | 200k |
| Cheapest output | $60/1M tokens | $80/1M tokens |
| Provider routes | 1 tracked | 3 tracked |
| Shared benchmarks | 0 shared | 0 shared |
Decision tradeoffs
- Nano Banana 2 (Gemini 3.1 Flash Image) has the lower cheapest tracked output price at $60/1M tokens.
- Local decision data tags Nano Banana 2 (Gemini 3.1 Flash Image) for Long context and Vision.
- o3-pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
- o3-pro has broader tracked provider coverage for fallback and procurement flexibility.
- o3-pro uniquely exposes Function calling, Tool use, and Structured outputs in local model data.
- Local decision data tags o3-pro for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Nano Banana 2 (Gemini 3.1 Flash Image)
$15,400
Cheapest tracked route/tier: Google AI Studio
o3-pro
$36,000
Cheapest tracked route/tier: OpenRouter
Estimated monthly gap: $20,600. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- No overlapping tracked provider route is sourced for Nano Banana 2 (Gemini 3.1 Flash Image) and o3-pro; plan for SDK, billing, or endpoint changes.
- o3-pro is $20/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- o3-pro adds Function calling, Tool use, and Structured outputs in local capability data.
- No overlapping tracked provider route is sourced for o3-pro and Nano Banana 2 (Gemini 3.1 Flash Image); plan for SDK, billing, or endpoint changes.
- Nano Banana 2 (Gemini 3.1 Flash Image) is $20/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Function calling, Tool use, and Structured outputs before moving production traffic.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-05-28 | 2025-06-10 |
| Context window | 131k | 200k |
| Parameters | — | — |
| Architecture | Decoder Only | Decoder Only |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Commercial use | Commercial use: conditional | Commercial use: conditional |
| Knowledge cutoff | 2025-01 | 2025-08 |
Pricing and availability
| Pricing attribute | Nano Banana 2 (Gemini 3.1 Flash Image) | o3-pro |
|---|---|---|
| Input price | $0.50/1M tokens | $20/1M tokens |
| Output price | $60/1M tokens | $80/1M tokens |
| Providers |
Capabilities
| Capability | Nano Banana 2 (Gemini 3.1 Flash Image) | o3-pro |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| Function calling | No | Yes |
| Tool use | No | Yes |
| Structured outputs | No | Yes |
| Code execution | No | Yes |
| 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 function calling: o3-pro, tool use: o3-pro, structured outputs: o3-pro, and code execution: o3-pro. Both models share vision, multimodal input, and reasoning mode, 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, Nano Banana 2 (Gemini 3.1 Flash Image) lists $0.50/1M input and $60/1M output tokens on the cheapest tracked provider, while o3-pro lists $20/1M input and $80/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Nano Banana 2 (Gemini 3.1 Flash Image) lower by about $19.65 per million blended tokens. Availability is 1 providers versus 3, so concentration risk also matters.
Choose Nano Banana 2 (Gemini 3.1 Flash Image) when vision-heavy evaluation and lower input-token cost are central to the workload. Choose o3-pro when coding workflow support, larger context windows, and broader provider choice 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, Nano Banana 2 (Gemini 3.1 Flash Image) or o3-pro?
o3-pro supports 200k 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, Nano Banana 2 (Gemini 3.1 Flash Image) or o3-pro?
Nano Banana 2 (Gemini 3.1 Flash Image) is cheaper on tracked token pricing. Nano Banana 2 (Gemini 3.1 Flash Image) costs $0.50/1M input and $60/1M output tokens. o3-pro costs $20/1M input and $80/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Nano Banana 2 (Gemini 3.1 Flash Image) or o3-pro open source?
Nano Banana 2 (Gemini 3.1 Flash Image) is listed under Proprietary. o3-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, Nano Banana 2 (Gemini 3.1 Flash Image) or o3-pro?
Both Nano Banana 2 (Gemini 3.1 Flash Image) and o3-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, Nano Banana 2 (Gemini 3.1 Flash Image) or o3-pro?
Both Nano Banana 2 (Gemini 3.1 Flash Image) and o3-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 Nano Banana 2 (Gemini 3.1 Flash Image) and o3-pro?
Nano Banana 2 (Gemini 3.1 Flash Image) is available on Google AI Studio. o3-pro is available on OpenRouter, OpenAI API, and Vercel AI Gateway. 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.