Stable Diffusion XL API Reference

Request body

Submit an async generation request. The model field selects the model; other fields are model-specific input parameters.

stringmodelrequired

Model identifier. Set to stability-ai/fast-sdxl/image-to-image.

Default: stability-ai/fast-sdxl/image-to-image

stringpromptrequired

The prompt to use for generating the image. Be as descriptive as possible for best results.

stringimagerequired

The URL of the image to use as a starting point for the generation.

Optional<number>guidance_scale

The CFG (Classifier Free Guidance) scale is a measure of how close you want the model to stick to your prompt when looking for a related image to show you.

Range: 0 to 20

Default: 7.5

Optional<integer>num_inference_steps

The number of inference steps to perform.

Range: 1 to 65

Default: 25

Optional<number>strength

determines how much the generated image resembles the initial image

Range: 0.05 to 1

Default: 0.95

Optional<boolean>preserve_aspect_ratio

If set to true, the aspect ratio of the generated image will be preserved even if the image size is too large. However, if the image is not a multiple of 32 in width or height, it will be resized to the nearest multiple of 32. By default, this snapping to the nearest multiple of 32 will not preserve the aspect ratio. Set crop_output to True, to crop the output to the proper aspect ratio after generating.

Default: false

Optional<array<object>>loras

The list of LoRA weights to use.

Default:

Optional<string>request_id

An id bound to a request, can be used with response to identify the request itself.

Default:

Optional<string>safety_checker_version

The version of the safety checker to use. v1 is the default CompVis safety checker. v2 uses a custom ViT model.

Allowed values: v1, v2

Default: v1

Optional<array<object>>embeddings

The list of embeddings to use.

Default:

Optional<boolean>crop_output

If set to true, the output cropped to the proper aspect ratio after generating.

Default: false

Optional<boolean>expand_prompt

If set to true, the prompt will be expanded with additional prompts.

Default: false

Optional<string>format

The format of the generated image.

Allowed values: jpeg, png

Default: jpeg

Optional<string>aspect_ratio

The aspect ratio of the generated image.

Allowed values: 21:9, 16:9, 3:2, 4:3, 5:4, 1:1, 4:5, 3:4, 2:3, 9:16

Optional<integer>seed

The same seed and the same prompt given to the same version of Stable Diffusion will output the same image every time.

Default: null

Response Schema

The submit endpoint returns an accepted generation task. Poll the result endpoint with the returned id for terminal outputs or errors.

Optional<string>error

Error message if the task failed. Empty on success.

stringidrequired

Unique identifier for the generation task.

Optional<string>model

Model ID used for the prediction.

Optional<array>outputs

Array of generated content. Empty when status is not completed.

stringstatusrequired

Status of the task: pending, running, completed, failed, or timeout.

Allowed values: pending, running, completed, failed, timeout

Model capabilities

array<string>capability_tagsrequired

Capabilities declared by the model registry.

Default: image-to-image

stringexecution_moderequired

Execution mode declared by the model registry.

Default: async

# 1. Submit a generation request curl -X POST https://api.sandbase.ai/v1/run \ -H "Authorization: Bearer $SANDBASE_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "model": "stability-ai/fast-sdxl/image-to-image", "prompt": "an island near sea, with seagulls, moon shining over the sea, light house, boats int he background, fish flying over the sea", "image": "https://fal-cdn.batuhan-941.workers.dev/files/tiger/IExuP-WICqaIesLZAZPur.jpeg", "aspect_ratio": "21:9" }' # 2. If the response is still running, poll the returned id curl https://api.sandbase.ai/v1/run/run_abc123 \ -H "Authorization: Bearer $SANDBASE_API_KEY"