[Black Forest Labs](/ai-gateway/models/labs/bfl)

# FLUX.2 \[klein\] 9B

FLUX.2 \[klein\] 9B is Black Forest Labs's quality-focused small image model in the Klein family. It pairs a 9B flow model with an 8B Qwen3 text embedder and distills inference to four steps for sub-half-second latency. Your use is subject to Black Forest Labs's [Terms](https://bfl.ai/legal/terms-of-service) & [Privacy](https://bfl.ai/legal/privacy-policy) Policies.

Image Gen

[Use with AI Gateway](https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Futm_source%3Dgateway-model-page%26utm_campaign%3Dai-gateway-models&title=Get+Started+with+Vercel+AI+Gateway) [View docs](https://vercel.com/docs/ai-gateway)

AI SDKChat Completions

```
1import { experimental_generateImage as generateImage } from 'ai';
2

3const result = await generateImage({
4  model: 'bfl/flux-2-klein-9b',
5  prompt: 'A red balloon on a wooden table.'
6});
```

[Read docs](https://vercel.com/docs/ai-gateway/sdks-and-apis/ai-sdk)

[Overview](/ai-gateway/models/flux-2-klein-9b) [About](/ai-gateway/models/flux-2-klein-9b/about) [Providers](/ai-gateway/models/flux-2-klein-9b/providers) [Similar](/ai-gateway/models/flux-2-klein-9b/similar) [FAQ](/ai-gateway/models/flux-2-klein-9b/faq)

## [Copy link to heading](#playground)Playground

Try out FLUX.2 \[klein\] 9B by Black Forest Labs. Usage is billed to your team at API rates. Free users (those who haven't made a payment) get $5 of credits every 30 days.

![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75)FLUX.2 \[klein\] 9B

Prompt

Describe what you want the model to generate.

Reference images(optional)

Add up to 4 images

Images to generate

1234

![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=96&q=75)

Your generated image will appear here

## [Copy link to heading](#providers)Providers

Route requests across multiple providers. Copy a provider slug to set your preference. Visit the [docs](/docs/ai-gateway/provider-options) for more info. Using a provider means you agree to their terms, listed under Legal.

| Provider |
| --- |

| Input | Output | Cache | Web Search | Capabilities | ZDR | No Training | Free Tier | Release Date |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |

| ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) [Black Forest Labs](/ai-gateway/models/providers/bfl) Legal:[Terms](https://bfl.ai/legal/terms-of-service)•[Privacy](https://bfl.ai/legal/privacy-policy) |  | $0.015/MP |  | — |  |  |  |  | 01/15/2026 |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |

## [Copy link to heading](#more-models-by-black-forest-labs)More models by Black Forest Labs

All

Image

Video

| Model |
| --- |

| Context | Latency | Throughput | Input | Output | Cache | Web Search | Capabilities | Providers | ZDR | No Training | Free Tier | Release Date |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |

| ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) [bfl/flux\-3-video](/ai-gateway/models/flux-3-video) |  |  |  |  | $0.06/sec+2 more |  | — |  | ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) |  |  |  | 08/04/2026 |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) [bfl/flux-2-klein-4b](/ai-gateway/models/flux-2-klein-4b) |  |  |  |  | $0.014/MP |  | — |  | ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) |  |  |  | 01/15/2026 |  |
| ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) [bfl/flux-2-flex](/ai-gateway/models/flux-2-flex) |  |  |  |  | $0.06/MP |  | — |  | ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) |  |  |  | 11/25/2025 |  |
| ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) [bfl/flux-kontext-max](/ai-gateway/models/flux-kontext-max) | 512 |  |  |  | $0.08/img |  | — |  | ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) |  |  |  | 05/29/2025 |  |
| ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) [bfl/flux-kontext-pro](/ai-gateway/models/flux-kontext-pro) | 512 |  |  |  | $0.04/img |  | — |  | ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) ![prodia logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fprodia.png&w=48&q=75) |  |  |  | 05/29/2025 |  |
| ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) [bfl/flux-pro-1.0-fill](/ai-gateway/models/flux-pro-1.0-fill) |  |  |  |  | $0.05/img |  | — |  | ![bfl logo](/vc-ap-vercel-marketing/_next/image?url=https%3A%2F%2F7nyt0uhk7sse4zvn.public.blob.vercel-storage.com%2Fdocs-assets%2Fstatic%2Fdocs%2Fai-gateway%2Flogos%2Fblackforestlabs.png&w=48&q=75) |  |  |  | 10/01/2024 |  |

## [Copy link to heading](#about-flux2-klein-9b)About FLUX.2 \[klein\] 9B

FLUX.2 \[klein\] 9B sits at the quality-focused end of Black Forest Labs's Klein family, released on January 15, 2026. Black Forest Labs describes it as setting the Pareto frontier for quality versus latency across text-to-image, single-reference editing, and multi-reference generation.

The architecture starts with the text encoder. Klein 9B pairs the flow model with an 8B Qwen3 embedder, a large-language-model-class text encoder that brings substantially better prompt understanding than smaller CLIP-based encoders. This Qwen3 integration is the primary reason Klein 9B understands complex, multi-clause prompts more accurately than competing small models.

The 9B flow model is step-distilled to four inference steps. Step distillation compresses the full diffusion trajectory into a small number of high-quality denoising passes. The result is a model that generates images in under half a second while retaining the quality of a much larger, slower undistilled counterpart.

Klein 9B handles text-to-image synthesis, image editing with a single reference, and multi-reference generation (combining multiple input images to blend concepts) within the same weights.

## [Copy link to heading](#what-to-consider-when-choosing-a-provider)What To Consider When Choosing a Provider

- Configuration: Klein 9B uses the FLUX Non-Commercial License (NCL). If you're building a commercial production application, consider Klein 4B (Apache 2.0) or FLUX.2 Pro instead. See N/A for current API pricing.
- Zero Data Retention: Zero Data Retention is offered on a per-provider and model basis. See the [documentation](https://vercel.com/docs/ai-gateway/security-and-compliance/zdr) for details.
- Authentication: AI Gateway authenticates requests using an [API key](https://vercel.com/docs/ai-gateway/authentication-and-byok#api-key-authentication) or [OIDC token](https://vercel.com/docs/ai-gateway/authentication-and-byok#oidc-token-authentication). You do not need to manage provider credentials directly.

## [Copy link to heading](#when-to-use-flux2-klein-9b)When to Use FLUX.2 \[klein\] 9B

### Best for

- Quality-latency sweet spot: Klein 9B fits when Klein 4B quality falls short but FLUX.2 Pro latency is too high
- Multi-reference generation: Workflows that combine multiple concept images into a coherent output at interactive speed
- Agentic visual systems: Sub-second latency enables rapid iteration loops that generate and evaluate images many times per session
- Prompt-heavy workflows: Complex, descriptive instructions benefit from the Qwen3 text embedder's language understanding

### Consider alternatives when

- Unrestricted commercial use: Klein 9B uses the FLUX Non-Commercial License, so choose Klein 4B (Apache 2.0) or FLUX.2 Pro instead
- Absolute maximum quality: FLUX.2 Pro and FLUX.2 Max deliver higher fidelity when latency is not the priority
- Masked region inpainting: FLUX.1 Fill Pro is specialized for mask-based fill rather than generative or instruction-based editing

## [Copy link to heading](#conclusion)Conclusion

FLUX.2 \[klein\] 9B combines an 8B Qwen3 text embedder, four-step distillation, and multi-reference support in a model that responds in under half a second. For teams building interactive visual applications or agent loops that iterate rapidly, Klein 9B delivers multi-reference editing at latencies many earlier fast image models did not match.