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What is FLUX 3 Image? The image model you lay out with boxes
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#AI models#FLUX 3 Image#FLUX 3 API#FLUX 3 pricing#Black Forest Labs#AI image editing API

What is FLUX 3 Image? The image model you lay out with boxes

Sadaf Masood

FLUX 3 Image is Black Forest Labs' new image model, released on 1 October 2026. It generates images from a prompt and edits existing images, all through one API endpoint. Its distinctive feature is layout control: you draw a bounding box for each element (a headline, a product, a face) and the model puts it there. Prices run from $0.041 to $0.607 per image depending on resolution, and are half that until 8 October.

If your product or workflow makes images to a fixed layout, such as banners, product shots, catalogue pages or social posts, this is the model to test this week, while the launch discount runs.

What can it do that earlier image models could not?

It lets you specify where things go, and it can change one part of an image without touching the rest. Black Forest Labs' release notes list five features:

  • Bounding boxes in the prompt. Each box is four numbers on a 0-1000 grid, plus a description of what goes inside it. You add them to the end of the prompt; there is no separate parameter.
  • Local edits. Mark one element and recolour, replace, move, resize or remove it. The rest of the image stays as it was. Several elements can change in one request.
  • Up to ten reference images. You refer to each one by its position in the prompt, for example "put the bottle from image 2 on the table in image 1".
  • Up to 4K output (about 16 megapixels) in 15 aspect ratios.
  • One endpoint. The prompt decides whether the request generates or edits. There is no mode switch.

Two defaults matter in production. First, grounding is on: the model searches the web and images before it generates, to get real things right. Set it to false for faster results that use only your prompt. Second, the finished image comes back as a signed URL that expires after one hour, so your code has to download it straight away.

What does it cost?

You pay per image, by output resolution, with no subscription. These are the prices on Black Forest Labs' pricing page and API docs, read on 3 October 2026. The launch offer runs from 1 October 15:00 UTC to 8 October 15:00 UTC.

ResolutionOutputPrice per imageLaunch offer
768sq768 × 768$0.041$0.0205
1kAbout 1 MP$0.048$0.024
1.5k1.5K$0.07$0.035
2kAbout 4 MP$0.100$0.05
4kAbout 16 MP$0.607$0.3035

A worked example: an online shop wants 400 product banners at 2K, and expects to generate three versions of each before keeping one. That is 400 × 3 = 1,200 images. At the list price, 1,200 × $0.100 = $120. During the launch offer, 1,200 × $0.05 = $60. Edits are billed as images too, so budget for the rounds of changes as well as the first drafts. Each API response includes the cost of the request, so you can track spend per job.

The jump to 4K is steep: one 4K image costs about six 2K images. For screens and social posts, 2K is usually enough. Keep 4K for print.

How do you get access?

FLUX 3 Image is available now through the BFL API and in the browser Playground. You need an API key from the BFL dashboard and prepaid credits (1 credit = $0.01). The official docs document the endpoint as POST https://api.bfl.ai/v1/flux-3-image, with the key in an x-key header. Only prompt is required. The request is asynchronous: you poll a returned URL until the status is Ready.

The weights are not public. Black Forest Labs offers FLUX 3 Image under a commercial weights licence for companies that want to fine-tune it and run it on their own servers; you arrange that through its sales team.

Plan for two failure states. Request Moderated means your prompt or an input image was blocked, and retrying the same request fails again. Content Moderated means the output was blocked. Your application needs a path for both, especially if end users write the prompts.

To have FLUX 3 Image built into your product or content workflow, with layouts, edit rounds and cost tracking set up for your catalogue, see what Vesprr builds or tell us about the job.

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