FLUX 3 Image

FLUX 3 Image is Black Forest Labs' image generation and editing model. Use model flux-3-image for text-to-image, single-image editing or multiple references. Each request returns one final image; this is not the FLUX 3 video model.

image_urls accepts up to 10 publicly accessible HTTP(S) URLs or base64 images. Adding references makes the request an editing or multi-reference task. References do not add a separate charge.

Resolutions are 768sq, 1k, 1.5k, 2k and 4k. Choose auto or one of 15 ratios from 21:9 to 9:21. Defaults are 1k and auto. Auto follows the first reference when editing; text-only generation follows the prompt or defaults to 1:1.

grounding defaults to true and allows upstream web or image retrieval before generation; set it to false to disable retrieval. safety_tolerance is an integer from 0 to 4, where 0 is strictest and the default is 2.

Layout and local-edit instructions belong in prompt, using the syntax described in the official documentation. The tool does not provide a visual bounding-box editor or a separate bbox parameter.

The price per image depends only on resolution. Aspect ratio and reference count do not change it. Use the platform price list for current rates and the completed task's cost for the final charge. Failed or moderation-blocked tasks are fully refunded.

POST /v1/images/generations returns a task_id. Query GET /v1/tasks/{task_id} until the task completes or fails, then retrieve the result image URL. A 4k task may take several minutes. Save results promptly and follow any expiry information returned.

Not without checking. This API does not accept width, height, pixel-size strings, seed, steps, guidance, output_format, negative_prompt or prompt_upsampling, and it does not generate multiple images per request. Choose resolution and aspect_ratio instead.