FLUX.1.1 [pro] Ultra
FLUX.1.1 [pro] Ultra is a high resolution text to image model from Black Forest Labs. It generates images up to 4 megapixels in about 10 seconds. Ultra mode targets sharp outputs. Raw mode targets natural photographic style. Built for API integration in real products.
![FLUX.1.1 [pro] Ultra](/docs/assets/555ea0e4-a483-4df8-bcef-60fc23cd7dde_SfWwg.webp)
API Options
Platform-level options for task execution and delivery.
-
taskType
string required value: imageInference -
Identifier for the type of task being performed
-
taskUUID
string required UUID v4 -
UUID v4 identifier for tracking tasks and matching async responses. Must be unique per task.
-
outputType
string default: URL -
Image output type.
Allowed values 3 values
-
outputFormat
string default: JPG -
Specifies the file format of the generated output. The available values depend on the task type and the specific model's capabilities.
- `JPG`: Best for photorealistic images with smaller file sizes (no transparency).
- `PNG`: Lossless compression, supports high quality and transparency (alpha channel).
- `WEBP`: Modern format providing superior compression and transparency support.
**Transparency**: If you are using features like background removal or LayerDiffuse that require transparency, you must select a format that supports an alpha channel (e.g., `PNG`, `WEBP`, `TIFF`). `JPG` does not support transparency.Allowed values 3 values
-
outputQuality
integer min: 20 max: 99 default: 95 -
Compression quality of the output. Higher values preserve quality but increase file size.
-
webhookURL
string URI -
Specifies a webhook URL where JSON responses will be sent via HTTP POST when generation tasks complete. For batch requests with multiple results, each completed item triggers a separate webhook call as it becomes available.
Learn more 1 resource
- Webhooks PLATFORM
- Webhooks
-
deliveryMethod
string default: sync -
Determines how the API delivers task results.
Allowed values 2 values
- Returns complete results directly in the API response.
- Returns an immediate acknowledgment with the task UUID. Poll for results using getResponse.
Learn more 1 resource
- Task Polling PLATFORM
-
uploadEndpoint
string URI -
Specifies a URL where the generated content will be automatically uploaded using the HTTP PUT method. The raw binary data of the media file is sent directly as the request body. For secure uploads to cloud storage, use presigned URLs that include temporary authentication credentials.
Common use cases:
- Cloud storage: Upload directly to S3 buckets, Google Cloud Storage, or Azure Blob Storage using presigned URLs.
- CDN integration: Upload to content delivery networks for immediate distribution.
// S3 presigned URL for secure upload https://your-bucket.s3.amazonaws.com/generated/content.mp4?X-Amz-Signature=abc123&X-Amz-Expires=3600 // Google Cloud Storage presigned URL https://storage.googleapis.com/your-bucket/content.jpg?X-Goog-Signature=xyz789 // Custom storage endpoint https://storage.example.com/uploads/generated-image.jpgThe content data will be sent as the request body to the specified URL when generation is complete.
-
safety
object -
Content safety checking configuration for image generation.
Properties 2 properties
-
safety»checkContentcheckContent
boolean default: false -
Enable or disable content safety checking. When enabled, defaults to
fastmode.
-
safety»modemode
string default: none -
Safety checking mode for image generation.
Allowed values 2 values
- Disables checking.
- Performs a single check.
-
-
ttl
integer min: 60 -
Time-to-live (TTL) in seconds for generated content. Only applies when
outputTypeisURL.
-
includeCost
boolean default: false -
Include task cost in the response.
-
numberResults
integer min: 1 max: 20 default: 1 -
Number of results to generate. Each result uses a different seed, producing variations of the same parameters.
Generation Parameters
Core parameters for controlling the generated content.
-
model
string required value: bfl:2@2 -
Identifier of the model to use for generation.
Learn more 3 resources
-
positivePrompt
string required min: 2 max: 3000 -
Text prompt describing elements to include in the generated output.
Learn more 2 resources
-
Width of the generated media in pixels.
Learn more 2 resources
-
Height of the generated media in pixels.
Learn more 2 resources
-
seed
integer min: 0 max: 9223372036854776000 -
Random seed for reproducible generation. When not provided, a random seed is generated in the unsigned 32-bit range.
Learn more 1 resource
Provider Settings
Parameters specific to this model provider. These must be nested inside the providerSettings.bfl object.
providerSettings.bfl object.-
providerSettings»bfl»promptUpsamplingpromptUpsampling
boolean default: false -
Enable automatic enhancement and expansion of the input prompt.
-
providerSettings»bfl»rawraw
boolean default: false -
Enable raw mode to produce images closer to direct model output without post-processing.
-
providerSettings»bfl»safetyTolerancesafetyTolerance
integer min: 0 max: 6 default: 2 -
Tolerance level for content moderation. Lower values are stricter; higher values are more permissive.
Wind-Carved Ice Harbor
{
"taskType": "imageInference",
"taskUUID": "17a2b204-94c7-4ae5-8c2d-369f6ed0eab6",
"model": "bfl:2@2",
"positivePrompt": "A vast polar harbor carved into layered blue ice, with towering cranes built from weathered timber and black steel, small cargo sleds gliding across frozen channels, bundled workers guiding shaggy draft animals, banners snapping in fierce wind, fractured ice reflecting pale sunrise, distant steam from boilers drifting into the cold air, gulls circling above, intricate frost textures, natural documentary-style photography, ultra-detailed surfaces, realistic scale, sharp focus, dramatic atmosphere, expansive composition, authentic color, no text, no watermark",
"width": 2752,
"height": 1536,
"seed": 33403,
"providerSettings": {
"bfl": {
"raw": true,
"promptUpsampling": true,
"safetyTolerance": 2
}
}
}{
"taskType": "imageInference",
"taskUUID": "17a2b204-94c7-4ae5-8c2d-369f6ed0eab6",
"imageUUID": "2337f8e5-5950-4428-99a0-746875c9c043",
"imageURL": "https://im.runware.ai/image/os/a19d05/ws/3/ii/2337f8e5-5950-4428-99a0-746875c9c043.jpg",
"seed": 33403,
"cost": 0.06
}Volcanic Glass Violinist Procession
{
"taskType": "imageInference",
"taskUUID": "dd08ddc3-a4ff-464a-b8b9-58f1e83733a3",
"model": "bfl:2@2",
"positivePrompt": "A towering ceremonial avenue carved through black volcanic stone, viewed in a vertical composition. At the center, an androgynous violinist in layered ash-gray robes performs while walking through a solemn procession of masked artisans carrying polished glass standards that catch fiery reflections. The violin itself is made of translucent obsidian and amber, glowing from trapped heat. Fine cinders drift through the air. In the distance, stepped basalt arches frame a glowing magma river, while suspended copper chimes and braided banners create depth overhead. Hyper-detailed textures: cracked stone, reflective glass, singed fabric edges, heat haze, metallic filigree, expressive faces beneath elegant masks. Dramatic cinematic lighting from lava and overcast smoke, rich contrast, precise anatomy, crisp micro-detail, epic scale, atmospheric perspective, premium editorial fantasy photography aesthetic.",
"width": 1344,
"height": 3136,
"seed": 48093,
"providerSettings": {
"bfl": {
"promptUpsampling": true,
"safetyTolerance": 2,
"raw": false
}
}
}{
"taskType": "imageInference",
"taskUUID": "dd08ddc3-a4ff-464a-b8b9-58f1e83733a3",
"imageUUID": "2a1f70ac-2743-42b6-9c54-e629bd39639d",
"imageURL": "https://im.runware.ai/image/os/a07d11/ws/3/ii/2a1f70ac-2743-42b6-9c54-e629bd39639d.jpg",
"seed": 48093,
"cost": 0.06
}Glasshouse Archive Under Aurora
{
"taskType": "imageInference",
"taskUUID": "6b14e961-adba-4065-9c13-255a428b752b",
"model": "bfl:2@2",
"positivePrompt": "A towering abandoned glasshouse transformed into a vertical archive of living plants and suspended manuscripts, rising through a remote polar valley beneath sweeping aurora bands. Fractured iron ribs, fogged panes, hanging ladders, spiral stair fragments, ivy-wrapped catalog plaques, shelves of weathered field journals sealed in glass capsules, rare alpine flowers blooming from cracked masonry, tiny warm lanterns placed along narrow catwalks, a shallow reflective pool at the base with scattered petals and fallen paper tags. Two small human figures in heavy expedition coats study the structure from below for scale. Hyper-detailed textures, intricate botanical variety, luminous sky gradients of emerald, violet, and pale gold, cinematic depth, razor-sharp architectural lines, elegant symmetry with organic overgrowth, majestic vertical composition, high realism with a slightly dreamlike fine-art sensibility.",
"width": 1344,
"height": 3136,
"seed": 70408,
"providerSettings": {
"bfl": {
"promptUpsampling": true,
"raw": false,
"safetyTolerance": 2
}
}
}{
"taskType": "imageInference",
"taskUUID": "6b14e961-adba-4065-9c13-255a428b752b",
"imageUUID": "4b301cc1-47c5-4b1d-b700-b4e0e88bd248",
"imageURL": "https://im.runware.ai/image/os/a08d21/ws/3/ii/4b301cc1-47c5-4b1d-b700-b4e0e88bd248.jpg",
"seed": 70408,
"cost": 0.06
}