Black Forest Labs: FLUX.1 Fill [pro]
black-forest-labs/flux-fill-pro
Access FLUX.1 Fill [pro] from Black Forest Labs using the Puter.js AI API.
Get Started
Model Card
FLUX.1 Fill [pro] is Black Forest Labs' production-grade inpainting and outpainting model, editing or expanding an image from a binary mask and a text prompt.
Black Forest Labs describes it as a state-of-the-art inpainting model, outperforming competing methods including Ideogram 2.0 at understanding complex scenes and text while keeping edits consistent with the rest of the image.
It handles object removal, adding new elements, and canvas expansion, preserving lighting and perspective around the edited region. It's served through the BFL API for production use, ahead of the open-weight Fill [dev] variant in output quality.
Cost Per Image $0.05
per generation
Configuration output
resolution
Release Date Nov 21, 2024
Code Example
Use FLUX.1 Fill [pro] in your app with the Puter.js AI API — no API keys or setup required.
// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';
puter.ai.txt2img("A serene mountain landscape at sunset", {
model: "black-forest-labs/flux-fill-pro"
}).then(image => {
document.body.appendChild(image);
});
<html>
<body>
<script src="https://js.puter.com/v2/"></script>
<script>
puter.ai.txt2img("A serene mountain landscape at sunset", {
model: "black-forest-labs/flux-fill-pro"
}).then(image => {
document.body.appendChild(image);
});
</script>
</body>
</html>
More AI Models From Black Forest Labs
Find other Black Forest Labs models →
FLUX 3
FLUX 3 is Black Forest Labs' multimodal foundation model, a change from the company's previous FLUX.1 and FLUX.2 releases, which were image-only. It is trained jointly on images, video, and audio using an architecture BFL calls Self-Flow, and is the company's first model to generate video and audio from the same set of weights. The video capability supports text-to-video, image-to-video, video-to-video editing, video continuation, and keyframe-based transitions, producing clips up to 20 seconds long in HD (1 megapixel per frame) or Full HD (2 megapixels per frame). It generates optional native audio alongside the video, including multilingual dialogue, sound effects, and ambient noise. Black Forest Labs reports FLUX 3 Video ranks highest in Elo ratings for text-to-video and image-to-video among models it compared, including Gemini Omni Flash, Minimax H3, and Seedance 2.0. FLUX 3 Video became generally available on August 5, 2026.
ImageFLUX.2 [klein] 4B
FLUX.2 Klein 4B is a compact, Apache 2.0 licensed model distilled from the full FLUX.2 architecture, capable of sub-second image generation on consumer GPUs with ~13GB VRAM. It supports text-to-image, image editing, and multi-reference generation in a unified model.
ImageFLUX.2 [klein] 9B
FLUX.2 Klein 9B is a larger variant of the Klein family built on a 9B flow model with an 8B Qwen3 text embedder, matching or exceeding models 5x its size in quality. It offers higher output diversity than the 4B distilled variant and is ideal for fine-tuning and research.
Frequently Asked Questions
You can access FLUX.1 Fill [pro] by Black Forest Labs through Puter.js AI API. Include the library in your web app or Node.js project and start making calls with just a few lines of JavaScript — no backend and no configuration required.
FLUX.1 Fill [pro] is free to integrate using the Puter.js AI API. With the User-Pays Model, you can add AI to your app for $0, since users cover their own AI usage through their Puter account.
| Price | |
|---|---|
| Per image | $0.05 |
FLUX.1 Fill [pro] was created by Black Forest Labs and released on Nov 21, 2024.
Yes — the FLUX.1 Fill [pro] API works with any JavaScript framework, Node.js, or plain HTML through Puter.js. Just include the library and start building. See the documentation for more details.
Add FLUX.1 Fill [pro] to your app for free
Developers can integrate FLUX.1 Fill [pro] for free using the Puter.js AI API.
With the User-Pays Model, each user covers their own AI usage instead of the developer.