Is Nano Banana 2 (Gemini 3.1 Flash Image Preview) available on FastMetal?

Not at the moment. GLM 5.3 Flash, from the same lab, is available on the FastMetal API today.

What is the context window of Nano Banana 2 (Gemini 3.1 Flash Image Preview)?

65,536 tokens, shared between the prompt and the response.

google/gemini-3-1-flash-image-preview

Not Available

Nano Banana 2 (Gemini 3.1 Flash Image Preview)

Gemini 3.1 Flash Image Preview, a.k.a. "Nano Banana 2," is Google’s latest state of the art image generation and editing model, delivering Pro-level visual quality at Flash speed. It combines advanced contextual understanding with fast, cost-efficient inference, making complex image generation and iterative edits significantly more accessible. Aspect ratios can be controlled with the [image_config API Parameter](https://openrouter.ai/docs/features/multimodal/image-generation#image-aspect-ratio-configuration)

2/26/2026

65,536 tokens

Specifications

Modalities

Input

image

text

Output

image

text

Supported Parameters

include_reasoning

max_tokens

reasoning

response_format

seed

stop

structured_outputs

temperature

top_p

Max Output Tokens

65,536

Reasoning Configuration

Default: Thinking on (effort: minimal)
Selectable effort levels: high
minimal
Turning thinking off: Possible (reasoning.enabled: false)

How to control thinking, and what it costs

Frequently asked questions

Is Nano Banana 2 (Gemini 3.1 Flash Image Preview) available on FastMetal?: Not at the moment. GLM 5.3 Flash, from the same lab, is available on the FastMetal API today.
What is the context window of Nano Banana 2 (Gemini 3.1 Flash Image Preview)?: 65,536 tokens, shared between the prompt and the response.

Models you can use on FastMetal