Image resolution, aspect ratio and quality are different controls
Avoid copying 4K or high-quality settings between incompatible models. Match output parameters to the chosen MaxAPI model and endpoint.
Technical review:
Separate the three decisions
Resolution describes output dimensions or a model-specific size tier. Aspect ratio describes the shape. Quality is a separate model option where supported; it is not a universal switch that makes every model sharper or larger. Choose the required layout first, then a valid size for that layout, and finally a supported quality value. A 4K tier does not mean that 4096 × 4096 is accepted by every image API.
Gemini: check the specific image variant
The current MaxAPI catalogue treats Gemini 3.1 Flash Lite Image and Gemini 2.5 Flash Image as 1K entries. The Gemini 3 Pro Image and Gemini 3.1 Flash Image entries expose higher-resolution options. On the JSON image interface, resolution and aspect_ratio describe these choices. On Gemini-native requests, consult the API tab for generationConfig.imageConfig.imageSize and aspectRatio instead. Do not mix both endpoint schemas into one request.
// MaxAPI JSON image fields for the Lite image example
{ "resolution": "1K", "aspect_ratio": "1:1", "n": 1 }GPT Image: use the generated dimension example
For GPT Image 2, the MaxAPI page maps resolution tiers and ratios to concrete width × height strings. Its 4K square selection currently uses 2880x2880, while 16:9 uses 3840x2160; it does not send 4096x4096. These are MaxAPI integration settings, not a claim that all providers interpret “4K” identically. Use the page’s generated API example to avoid combining an arbitrary width, height and tier. Quality choices must come from that model’s own options.
Validate output and cost, not just acceptance
A request accepted by the gateway is not proof that the final file has your intended dimensions, crop or visual quality. After a successful test, inspect the decoded output dimensions and the actual billed record. Change one parameter at a time when comparing results, keep the same authorized reference material, and label any comparison with the model, route, date and parameters. Do not infer cost by multiplying a public “starting from” price across different quality or billing units.
Model-specific parameters
Public configuration snapshot; not live availability. Follow each model page for its parameters, supported routes and reference limits.
- Gemini 3.1 Flash Lite Image
google/gemini-3.1-flash-lite-image - Gemini 3.1 Flash Image Preview
google/gemini-3.1-flash-image-preview - Nanobanana Pro
google/gemini-3-pro-image-preview - GPT Image 2
openai/gpt-image-2