gemini-3.1-flash-image-preview (Nano Banana 2) features professional-grade visual intelligence, lightning-fast efficiency, and realistic, grounded generative capabilities. This model serves as the high-efficiency counterpart to Gemini 3 Pro Image, optimized for speed and high-volume developer use cases.
Gemini 3.1 Flash Image Preview vs Gemini 3.1 Flash Image Preview (free)
Compare Gemini 3.1 Flash Image Preview from Google and Gemini 3.1 Flash Image Preview (free) from Google on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
This model is the free trial version of gemini-3.1-flash-image-preview (officially marketed as Nano Banana 2). To ensure stable service operation, usage limits have been set and resources are limited and may not be available at all times. For a stable version, please choose the official release; the request name for the official release is: gemini-3.1-flash-image-preview.
Pricing & Specifications
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
Promotional prices show the discounted rate; see each model page for promotion windows.
Activity Past 30 Days
Daily traffic served through AIHubMix — how demand for each model is trending.
Tokens / day
Requests / day
Performance Past 3 Days
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
Throughput (tok/s)
TTFT (s)
Uptime (%)
Cost calculator
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
FAQ
Which responds faster?
Gemini 3.1 Flash Image Preview: 10.1s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
Which one generates tokens faster?
Gemini 3.1 Flash Image Preview at 122.4 tok/s and Gemini 3.1 Flash Image Preview (free) at 34.2 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
What inputs and capabilities does each model support?
Gemini 3.1 Flash Image Preview accepts text and image input and supports thinking; Gemini 3.1 Flash Image Preview (free) accepts text and image input.
Can I call Gemini 3.1 Flash Image Preview and Gemini 3.1 Flash Image Preview (free) with the same API key?
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
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