FLUX.1 Fill Dev LoRA API reference

Call FLUX.1 Fill Dev LoRA from your own code with one PopNow API key. Below are the exact model IDs to send, every input field the model accepts, what each request costs in credits, and a request you can paste into a terminal.

At a glance

Made by: Black Forest Labs
Output: Image
From: 6.3 credits per image ($0.063)
Model IDs: black-forest-labs/flux-1-fill-dev-lora/edit

1 credit = $0.01. A task holds the highest possible charge when it is accepted and settles the real amount when it finishes, rounded up to whole credits; failed tasks are not charged. Ask POST /api/v1/jobs/quote for the exact figure before you run.

Edit Image

black-forest-labs/flux-1-fill-dev-lora/edit

Price

Option	Credits (per image)	US dollars
`Default`	6.3	$0.063

Parameters

Field	Type	Default	Allowed	What it does
`prompt`Required	`string`	—	up to 5,000 characters	Describe what belongs in the white area of the mask, in the light and style of the rest of the picture.
`image_url`Required	`string (uri)`	—	—	Source image to repaint. The result keeps its aspect ratio.
`mask_url`Required	`string (uri)`	—	—	Black-and-white mask the size of the source: white areas are redrawn, black areas are kept.
`resolution`Optional	`string`	`1k`	1k, 1.5k	Length of the output's long side: 1k is 1024 pixels, 1.5k is 1536. The source's aspect ratio is kept.
`num_outputs`Optional	`integer`	`1`	1 to 4	How many images to generate in one run, from 1 to 4.
`loras`Optional	`array<object>`	`[]`	up to 3 items	Up to three LoRA weight files trained for FLUX.1 dev, each with its own strength.
`guidance_scale`Optional	`number`	`30`	28 to 35	How closely the filled area follows the prompt, from 28 to 35.
`steps`Optional	`integer`	`28`	1 to 50	Denoising steps, from 1 to 50. Fewer steps return faster and a little softer.
`seed`Optional	`integer`	—	0 to 2147483647	Random seed for controlled comparisons.

Example request

This request runs as it is; any field you leave out uses its default. Put your key in POPNOW_API_KEY first.

The example uses PopNow sample files in image_url, mask_url. Replace them with your own public HTTPS links, uploads or saved assets.

POST /api/v1/jobs/createTask

curl -X POST "https://api.popnow.ai/api/v1/jobs/createTask" \
  -H "Authorization: Bearer $POPNOW_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{
  "model": "black-forest-labs/flux-1-fill-dev-lora/edit",
  "input": {
    "prompt": "Change the orange jacket to deep forest green and add soft golden-hour light; keep the face, pose and background unchanged",
    "image_url": "https://media.popnow.ai/influencer/examples/marco.webp",
    "mask_url": "https://media.popnow.ai/influencer/examples/marco.webp",
    "num_outputs": 1
  }
}'

The response carries a taskId straight away. Read the result with GET /api/v1/jobs/recordInfo, or add callBackUrl to be notified.

GET /api/v1/jobs/recordInfo

curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=TASK_ID_FROM_CREATE_TASK" \
  -H "Authorization: Bearer $POPNOW_API_KEY"