> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zerogen.com/llms.txt
> Use this file to discover all available pages before exploring further.

# FLUX

> Black Forest Labs' image models: FLUX.3 Image for detail and legible text, and FLUX.2 Pro.

FLUX, from Black Forest Labs, makes and edits images. Add reference images and
it edits or combines them.

| Model | Best for | Sizes |
| - | - | - |
| **FLUX.3 Image** | Detailed compositions and legible text | 1K, 2K or 4K |
| **FLUX.2 Pro** | Quick images up to 1 megapixel | Fixed sizes up to 1 megapixel |

## What you can give it

* **A prompt**.
* **References**: up to 10 images on FLUX.3 Image, or 9 on FLUX.2 Pro.

## Output settings

**FLUX.3 Image**

* **Aspect ratio**: Auto, 1:1, 3:2, 2:3, 4:3, 4:5, 3:4, 16:9, 9:16 or 21:9.
  Auto makes a square image, or follows the first reference when editing.
* **Resolution**: 1K, the default, 2K or 4K.

**FLUX.2 Pro**

* **Aspect ratio**: Auto, 1:1, 3:2, 2:3, 4:3, 3:4, 16:9 or 9:16, each up to 1
  megapixel. 3:2 comes out as 4:3, and 2:3 as 3:4.
* When editing, Auto follows the first reference, up to 4 megapixels.

Each run makes one image.

## Cost

* **FLUX.3 Image** is priced per megapixel of the result, and references are
  free. A 1K square image costs about $0.07, 2K about $0.25 and 4K about
  \$1.00.
* **FLUX.2 Pro** costs about \$0.04 for a 1-megapixel image. Edits also count
  the references' size.

Prices are as of October 28, 2026.

For FLUX.3 video, see [FLUX.3 video](https://docs.zerogen.com/models/flux-video.md).


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