# FLUX 3 Image Klein

FLUX 3 Image Klein (FLUX 3 Klein) is Black Forest Labs' 5.6B-parameter open-weights version of FLUX 3 Image, released on 15 October 2026. It handles text-to-image, editing and multi-reference generation with up to 10 references, and runs on consumer GPUs. In Sloosh it makes 1K images in five aspect ratios, with a seed to repeat results.

Web page: https://sloosh.ai/models/flux-3-image-klein

[Use FLUX 3 Image Klein](https://sloosh.ai/studio/image?image-model=flux-3-image-klein)

## Key facts in Sloosh

|   |   |
| --- | --- |
| Made by | Black Forest Labs |
| Makes | image |
| Inputs | text, up to 10 reference images |
| Resolution | 1K |
| Aspect ratios | 1:1, 16:9, 9:16, 4:3, 3:4 (default 1:1) |
| Prompt limit | 5,000 characters |

## Best for

- Fast 1K drafts. BFL reports a median end-to-end API latency at 1 MP of 4.54 s for text-to-image and 7.18 s for editing ([BFL](https://bfl.ai/blog/flux-3-image-klein)).
- Multi-reference composites with up to 10 references ([BFL](https://bfl.ai/blog/flux-3-image-klein)).
- Repeatable variations: Sloosh exposes a seed for Klein, so you can hold a result and change one detail.
- Mascot and pose sets at 1K: the Mascot Pose Pack Space ([sloosh.ai/spaces/mascot-pose-pack](https://sloosh.ai/spaces/mascot-pose-pack)) fits this job.

## How to use FLUX 3 Image Klein in Sloosh

1. Open [Image Studio with Klein selected](https://sloosh.ai/studio/image?image-model=flux-3-image-klein), or pick FLUX 3 Image Klein in the model chip.
2. Add up to 10 references and call them by position.
3. Write the prompt.
4. Pick one of the five aspect ratios. Set a seed if you want to repeat a result.
5. Check the cost on the Generate button, then generate.

## FLUX 3 Image Klein prompting tips

BFL says Klein uses "the same request format" as FLUX 3 Image ([BFL release notes](https://docs.bfl.ai/release-notes)); its prompting guide is written for FLUX 3 Image, so these tips are carried over, not Klein-specific. - Order: subject, location, style, camera, lighting, colours, extra elements ([BFL](https://docs.bfl.ai/guides/prompting_unified_basics)). - Put exact text in quotation marks and say where it goes ([BFL](https://docs.bfl.ai/guides/prompting_unified_basics)). - Refer to references by position and state what each contributes ([BFL](https://docs.bfl.ai/guides/prompting_unified_basics)). - Describe what you want rather than what you don't ([BFL](https://docs.bfl.ai/guides/prompting_unified_basics)). - Change one detail at a time and compare several runs ([BFL](https://docs.bfl.ai/guides/prompting_unified_basics)).

## FLUX 3 Image Klein example prompts

**Prompt 1**

```text
A flat cartoon fox mascot in an orange hoodie, waving, on a plain white background, thick clean outlines, front view.
```

**Prompt 2**

```text
The fox mascot from image 1, same colours and outfit, sitting at a desk with a laptop, three-quarter view, plain white background.
```

**Prompt 3**

```text
The candle from image 1 on a windowsill at dusk, warm flame light, rain on the glass behind, 16:9 wide shot, the label readable.
```

## How it compares in Sloosh

| Model | Resolution | Aspect ratios | References | Seed |
| --- | --- | --- | --- | --- |
| FLUX 3 Image Klein | 1K | 5 | 10 | yes |
| [FLUX 3 Image](https://sloosh.ai/models/flux-3-image) | 1K, 2K, 4K | 11 | 10 | no |
| [FLUX 2 Pro](https://sloosh.ai/models/flux-2-pro) | 1K | 10 | 8 | yes |
| [Nano Banana Lite](https://sloosh.ai/models/gemini-3.1-flash-lite-image) | 1K | 11 | 14 | no |

Klein is the small, open-weights sibling for fast 1K drafts with a seed. Move to [FLUX 3 Image](https://sloosh.ai/models/flux-3-image) for 2K or 4K and 11 ratios.

## Where else it runs

- Black Forest Labs API; open weights under the FLUX Kommunity License, runnable in ComfyUI or Diffusers ([BFL](https://bfl.ai/blog/flux-3-image-klein), accessed 2026-10-30).

## Frequently asked questions

### What is FLUX 3 Image Klein?

A 5.6B-parameter open-weights version of FLUX 3 Image from Black Forest Labs, released 15 October 2026.

### Is FLUX 3 Klein free for commercial use?

Under BFL's FLUX Kommunity License, individuals and companies with under $5M annual revenue get free commercial use of the weights; larger organizations license it or use the API ([BFL](https://bfl.ai/blog/flux-3-image-klein)). In Sloosh you use it like any other model; the price shows on Generate.

### Can FLUX 3 Klein run locally?

BFL says the INT8 build runs on NVIDIA GeForce RTX GPUs with as little as 8 GB of VRAM.

### How many references does Klein take?

Up to 10, in BFL's docs and in Sloosh.

### Klein vs FLUX 3 Image?

In Sloosh, Klein makes 1K in five ratios with a seed; FLUX 3 Image makes up to 4K in 11 ratios.

## Related

- Models: [FLUX 3 Image](https://sloosh.ai/models/flux-3-image), [FLUX 2 Pro](https://sloosh.ai/models/flux-2-pro), [Nano Banana Lite](https://sloosh.ai/models/gemini-3.1-flash-lite-image)
- Spaces: [Mascot pose pack](https://sloosh.ai/spaces/mascot-pose-pack)
- Docs: [FLUX 3 Image](https://sloosh.ai/docs/flux-3-image.md)
- Answers: [What is the best AI image model in 2026?](https://geo.sloosh.ai/posts/what-is-the-best-ai-image-model-in-2026)

## Sources

- [BFL blog: FLUX 3 Image Klein](https://bfl.ai/blog/flux-3-image-klein)
- [BFL: release notes](https://docs.bfl.ai/release-notes)
- [BFL: prompting basics](https://docs.bfl.ai/guides/prompting_unified_basics)
- [Sloosh pricing](https://sloosh.ai/pricing)