---
title: "Generate an image with FLUX 1.1 [pro] finetune with ultra mode."
method: POST
path: "/v1/flux-pro-1.1-ultra-finetuned"
tags: ["Models"]
---

# Generate an image with FLUX 1.1 \[pro\] finetune with ultra mode.

`POST /v1/flux-pro-1.1-ultra-finetuned`

## Request

- Base URL: `https://api.bfl.ai`
- URL: `https://api.bfl.ai/v1/flux-pro-1.1-ultra-finetuned`
- Auth: API key in header `x-key`
- TypeScript: <https://skmtc.dev/bfl/apis/bfl-api/docs/v1/flux-pro-1.1-ultra-finetuned/post.ts> (a function with typed inputs; its response is checked against the schema)

Submits an image generation task with FLUX 1.1 [pro] finetune with ultra mode.

## Request body

- FinetuneFluxUltraInput
  - `user` string, nullable: Opaque identifier for the end user supplied by the calling platform.
  - `finetune_id` string, required: Name of the LoRA to use. For LoRAs from other organizations (public or shared), use the format 'org-id/lora-name'.
  - `finetune_strength` number: Strength of the fine-tuned model. 0.0 means no influence, 1.0 means full influence. Allowed values up to 2.0
  - `prompt` string, nullable: The prompt to use for image generation.
  - `seed` integer, nullable: Optional seed for reproducibility. If not provided, a random seed will be used.
  - `aspect_ratio` string: Aspect ratio of the image between 21:9 and 9:21
  - `safety_tolerance` integer: Tolerance level for input and output moderation. Between 0 and 6, 0 being most strict, 6 being least strict.
  - `output_format` 'jpeg' | 'png' | 'webp'
  - `image_prompt` string, nullable: Optional image to remix in base64 format
  - `image_prompt_strength` number: Blend between the prompt and the image prompt
  - `prompt_upsampling` boolean: Whether to perform upsampling on the prompt. If active, automatically modifies the prompt for more creative generation
  - `webhook_url` string, uri, nullable: URL to receive webhook notifications
  - `webhook_secret` string, nullable: Optional secret for webhook signature verification

## Response `200`

Successful Response

- union
  - AsyncResponse
    - `id` string, required
    - `polling_url` string, required
    - `cost` number, nullable: Cost in credits for this request
    - `input_mp` number, nullable: Input megapixels (2 decimal places)
    - `output_mp` number, nullable: Output megapixels (2 decimal places)
  - AsyncWebhookResponse
    - `id` string, required
    - `status` string, required
    - `webhook_url` string, required
    - `cost` number, nullable: Cost in credits for this request
    - `input_mp` number, nullable: Input megapixels (2 decimal places)
    - `output_mp` number, nullable: Output megapixels (2 decimal places)

## Other responses

- `422`: Validation Error

## Changes

- **2026-10-21** `ab75e0a84610`: 1 info
  - added the new optional request property `user`

[Operation history](https://skmtc.dev/bfl/apis/bfl-api/changes/v1/flux-pro-1.1-ultra-finetuned/post.md)

---

[API](https://skmtc.dev/bfl/apis/bfl-api.md) - [All operations](https://skmtc.dev/bfl/apis/bfl-api/llms.txt) - [OpenAPI document](https://skmtc.dev/bfl/apis/bfl-api/revisions/ea458c661ef8?raw)