What is FLUX.2 Klein 4B API?
Compact 4B FLUX.2 model optimized for efficient generation.
Technical Specifications
- Supported inputs: Image, Text
- Output: Image
- Endpoint: /images/generations
Performance Benchmarks
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FLUX.2 Klein 4B API Pricing
- Pricing on request
Where to Use FLUX.2 Klein 4B
High-volume image generation
Produce product visuals, thumbnails, and marketing assets programmatically at scale.
Creative and concept art
Turn text prompts into illustrations, mockups, and design explorations.
Image editing and variations
Provide a reference image to guide edits, restyles, or variations.
Code Sample
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Measured on the AI/ML API gateway across live traffic. Figures are medians unless stated. Last updated 2026-10-12.
FLUX.2 Klein 4B is documented as suited to interactive applications, real-time previews, and latency-critical production use cases.
It is also documented as suitable for content creation and rapid prototyping, especially where low-latency generation is important.
The model is documented for image generation from text descriptions, making text-to-image workflows a stated use case.
It is documented for image editing and multi-reference editing, including tasks such as inpainting, style transfer, and object manipulation.
import requests r = requests.post( "https://api.aimlapi.com/v1/images/generations", headers={"Authorization": "Bearer " + AIMLAPI_KEY}, json={ "model": "blackforestlabs/flux-2-klein-4b", "prompt": "A cat holding a sign that says hello" }, ) print(r.json())
const r = await fetch("https://api.aimlapi.com/v1/images/generations", { method: "POST", headers: { Authorization: `Bearer ${process.env.AIMLAPI_KEY}`, "Content-Type": "application/json", }, body: JSON.stringify({ "model": "blackforestlabs/flux-2-klein-4b", "prompt": "A cat holding a sign that says hello" }), }); console.log(await r.json());
curl -X POST https://api.aimlapi.com/v1/images/generations \ -H "Authorization: Bearer $AIMLAPI_KEY" \ -H "Content-Type: application/json" \ -d '{"model":"blackforestlabs/flux-2-klein-4b","prompt":"A cat holding a sign that says hello"}'
OpenAI-compatible — swap the base URL and it works with your existing SDK.
| Type | Price |
|---|---|
| Output | |
| Benchmark | Score | What it measures | Source | Retrieved |
|---|---|---|---|---|
| Text-to-Image Arena | 864 | Human preference Elo from blind pairwise comparisons of generated images, measured independently by Artificial Analysis | Source | September 28, 2026 |
| Model | Input | Output | Context | Best for |
|---|---|---|---|---|
FLUX.2 Klein 4B This page | Image generation at scale | |||
| Image generation at scale | ||||
| Image generation at scale | ||||
| Image generation at scale | ||||
| Image generation at scale |
FLUX.2 Klein 4B takes image, text as input and returns image.
FLUX.2 Klein 4B became available on June 12, 2026.
FLUX.2 Klein 4B is priced at $0.0182 / MP (variable).
FLUX.2 Klein 4B is billed per generation — a fixed charge per output rather than by prompt length.
Yes, FLUX.2 Klein 4B accepts image input as well as a text prompt.
FLUX.2 Klein 4B was built by Black Forest Labs.
Send a request to https://api.aimlapi.com/v1/images/generations with blackforestlabs/flux-2-klein-4b as the model id.
Yes. FLUX.2 Klein 4B is served through AI/ML API, so the same key and endpoint format used for other models applies.
FLUX.2 Klein 4B is a 4 billion parameter model, as indicated by its name.
It is a compact 4B version of FLUX.2 built for efficient image generation.
