Flux 1.1 Pro Ultra | AI Playground
Deliver high-resolution photorealism with fast generation, natural raw mode, and flexible styles for precise textures, dynamic lighting, and expressive artistic control.
Table of contents
1. Get started
Use RunComfy's API to run blackforestlabs/flux-1-1-pro/ultra/text-to-image. For accepted inputs and outputs, see the model's schema.
curl --request POST \
--url https://model-api.runcomfy.net/v1/models/blackforestlabs/flux-1-1-pro/ultra/text-to-image \
--header "Content-Type: application/json" \
--header "Authorization: Bearer <token>" \
--data '{
"prompt": "A microscopic view of spider silk, showing the fine, delicate fibers woven into a complex web structure. The individual strands glisten in the morning dew, with tiny droplets of water clinging to the silk. The image captures the astonishing strength and delicacy of spider silk, highlighting its organic beauty and precision."
}'2. Authentication
Set the YOUR_API_TOKEN environment variable with your API key (manage keys in your Profile) and include it on every request as a Bearer token via the Authorization header: Authorization: Bearer $YOUR_API_TOKEN.
3. API reference
Submit a request
Submit an asynchronous generation job and immediately receive a request_id plus URLs to check status, fetch results, and cancel.
curl --request POST \
--url https://model-api.runcomfy.net/v1/models/blackforestlabs/flux-1-1-pro/ultra/text-to-image \
--header "Content-Type: application/json" \
--header "Authorization: Bearer <token>" \
--data '{
"prompt": "A microscopic view of spider silk, showing the fine, delicate fibers woven into a complex web structure. The individual strands glisten in the morning dew, with tiny droplets of water clinging to the silk. The image captures the astonishing strength and delicacy of spider silk, highlighting its organic beauty and precision."
}'Monitor request status
Fetch the current state for a request_id ("in_queue", "in_progress", "completed", or "cancelled").
curl --request GET \
--url https://model-api.runcomfy.net/v1/requests/{request_id}/status \
--header "Authorization: Bearer <token>"Retrieve request results
Retrieve the final outputs and metadata for the given request_id; if the job is not complete, the response returns the current state so you can continue polling.
curl --request GET \
--url https://model-api.runcomfy.net/v1/requests/{request_id}/result \
--header "Authorization: Bearer <token>"Cancel a request
Cancel a queued job by request_id, in-progress jobs cannot be cancelled.
curl --request POST \
--url https://model-api.runcomfy.net/v1/requests/{request_id}/cancel \
--header "Authorization: Bearer <token>"4. File inputs
Hosted file (URL)
Provide a publicly reachable HTTPS URL. Ensure the host allows server‑side fetches (no login/cookies required) and isn't rate‑limited or blocking bots. Recommended limits: images ≤ 50 MB (~4K), videos ≤ 100 MB (~2–5 min @ 720p). Prefer stable or pre‑signed URLs for private assets.
5. Schema
Input schema
{
"type": "object",
"title": "Input",
"required": [
"prompt"
],
"properties": {
"prompt": {
"title": "Prompt",
"description": "",
"type": "string",
"default": "A microscopic view of spider silk, showing the fine, delicate fibers woven into a complex web structure. The individual strands glisten in the morning dew, with tiny droplets of water clinging to the silk. The image captures the astonishing strength and delicacy of spider silk, highlighting its organic beauty and precision."
},
"aspect_ratio": {
"title": "Aspect Ratio (W:H)",
"description": "",
"type": "string",
"enum": [
"21:9",
"16:9",
"4:3",
"1:1",
"3:4",
"9:16",
"9:21"
],
"default": "16:9"
},
"seed": {
"title": "Seed",
"description": "",
"type": "integer",
"default": 90290776
},
"raw": {
"title": "Raw Mode",
"description": "Enabling raw mode means generating images that are less processed and more natural-looking.",
"type": "boolean",
"default": false
}
}
}Output schema
{
"output": {
"type": "object",
"properties": {
"image": {
"type": "string",
"format": "uri",
"description": "single image URL"
},
"video": {
"type": "string",
"format": "uri",
"description": "single video URL"
},
"images": {
"type": "array",
"description": "multiple image URLs",
"items": { "type": "string", "format": "uri" }
},
"videos": {
"type": "array",
"description": "multiple video URLs",
"items": { "type": "string", "format": "uri" }
}
}
}
}