Flux 2 Klein Base 9B Edit | Fast Image Editing API

WaveSpeed AI FLUX.2 Klein Base 9B Edit

WaveSpeed AI FLUX.2 Klein Base 9B Edit is a high-quality image editing model built for prompt-driven transformations, compositing, and style changes. Upload one or more source images, describe the edit in natural language, and generate polished results with stronger detail and better prompt understanding than the 4B variant.

Why Choose This?

Higher-quality editing The 9B parameter model delivers richer detail, stronger prompt adherence, and better overall edit quality than the 4B variant.
Natural-language editing Describe the change you want in plain language — transform style, replace elements, change mood, or combine multiple images.
Multi-image support Upload multiple reference images and perform compositing or cross-image edits such as “Put the person in image1 into image2.”
Flexible output sizing Optionally set output dimensions, or leave size empty to preserve the original input dimensions.
Prompt Enhancer Built-in prompt enhancement can help improve edit quality and clarity.
Production-ready workflow Suitable for high-quality creative editing, marketing visuals, and more complex multi-image transformations.

Parameters

Parameter	Required	Description
prompt	Yes	Text description of the desired edit.
images	Yes	Source images to edit. Multiple images are supported.
size	No	Output dimensions. Leave empty to match the input image dimensions.
seed	No	Random seed for reproducibility. Use `-1` for random generation.

How to Use

Write your prompt — describe the edit you want, such as “Put the person in image1 into image2” or “Change this to watercolor style.”
Upload your images — add one or more source images using the image input.
Set size (optional) — specify output dimensions, or leave it empty to preserve the original dimensions.
Set seed (optional) — use -1 for random generation, or enter a fixed seed for reproducible results.
Submit — run the model and download the edited image.

Example Prompt

Put the person in image1 into image2, keep realistic lighting and proportions, and match the scene naturally.

Pricing

Item	Cost
Per image	$0.021

Billing Rules

Pricing is fixed at $0.021 per generated image
size and seed do not affect pricing
Flat-rate pricing applies regardless of image dimensions

Best Use Cases

Image compositing — Combine subjects or objects from multiple images into one result.
Style transfer — Transform images into different artistic or visual styles with strong fidelity.
Professional editing — Use the 9B model when the 4B variant is not sufficient for production-quality work.
Content transformation — Change lighting, mood, environment, or visual theme with more precision.
Complex multi-image edits — Handle edits that require stronger scene understanding and better subject consistency.

Pro Tips

Be specific about what should change and what should stay the same.
Reference input images clearly in the prompt, such as image1, image2, and so on.
Leave size empty when you want to preserve the original image dimensions.
Use the same seed when comparing different prompt variations on the same images.
For complex edits, describe both the main transformation and any constraints like lighting, realism, or identity preservation.

Notes

Both prompt and images are required.
If size is not specified, the output matches the input image dimensions.
The 9B model offers better detail and stronger prompt understanding than the 4B variant.
Need LoRA support? Try FLUX.2 Klein Base 9B Edit LoRA.

Related Models

FLUX.2 Klein Base 9B Edit LoRA — Edit with LoRA support for custom styles and more specialized control.
FLUX.2 Klein 4B Edit — Lighter 4B version with lower cost.
FLUX.2 Klein Base 9B Text-to-Image — Generate images directly from text prompts.

Flux 2 Klein Base 9b Edit API — Quick start

Grab a WaveSpeedAI API key, then call POST https://api.wavespeed.ai/api/v3/wavespeed-ai/flux-2-klein-base-9b/edit with your input as JSON. The endpoint returns a prediction id; poll the prediction endpoint until status flips to completed, then read the output URL from data.outputs[0]. Examples for Flux 2 Klein Base 9b Edit below.

HTTP example

# Submit the prediction
curl -X POST "https://api.wavespeed.ai/api/v3/wavespeed-ai/flux-2-klein-base-9b/edit" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $WAVESPEED_API_KEY" \
  -d '{
    "prompt": "A cinematic shot of a city at sunset, soft golden light",
    "seed": -1,
    "enable_sync_mode": false,
    "enable_base64_output": false
}'

# Response includes a prediction id. Poll for the result:
curl -X GET "https://api.wavespeed.ai/api/v3/predictions/{request_id}/result" \
  -H "Authorization: Bearer $WAVESPEED_API_KEY"

# When status is "completed", read the output from data.outputs[0].

Node.js example

// npm install wavespeed
const WaveSpeed = require('wavespeed');

const client = new WaveSpeed(); // reads WAVESPEED_API_KEY from env

const result = await client.run("wavespeed-ai/flux-2-klein-base-9b/edit", {
        "prompt": "A cinematic shot of a city at sunset, soft golden light",
        "seed": -1,
        "enable_sync_mode": false,
        "enable_base64_output": false
});

console.log(result.outputs[0]); // → URL of the generated output

Python example

# pip install wavespeed
import wavespeed

output = wavespeed.run(
    "wavespeed-ai/flux-2-klein-base-9b/edit",
    {
    "prompt": "A cinematic shot of a city at sunset, soft golden light",
    "seed": -1,
    "enable_sync_mode": false,
    "enable_base64_output": false
}
)

print(output["outputs"][0])  # → URL of the generated output

Flux 2 Klein Base 9b Edit API — Frequently asked questions

What is the Flux 2 Klein Base 9b Edit API?

Flux 2 Klein Base 9b Edit is a WaveSpeedAI model for image editing, exposed as a REST API on WaveSpeedAI. FLUX.2 [klein] Base 9B Edit is a high-quality image editing model with 9B parameters, offering precise modifications using natural language instructions. Ready-to-use REST inference API, best performance, no cold starts, affordable pricing. You can call it programmatically or try it from the playground above.

How do I call the Flux 2 Klein Base 9b Edit API?

POST your input parameters to the model's REST endpoint (shown in the API tab of this playground) with your WaveSpeedAI API key in the Authorization header. Submission returns a prediction ID; poll the prediction endpoint until status flips to "completed", then read the output URL from the result. The playground generates a ready-to-paste code sample in Python, JavaScript, or cURL for whatever inputs you've set. Full request/response shape is documented at https://wavespeed.ai/docs/docs-api/wavespeed-ai/flux-2-klein-base-9b-edit.

How much does Flux 2 Klein Base 9b Edit cost per run?

Flux 2 Klein Base 9b Edit starts at $0.021 per run. That figure is the base price — the final charge scales with the parameters you set in the form (output size, length, count, references, or whatever knobs this model exposes), so a higher-quality or larger output costs more than a minimal one. The exact cost for your current input is shown live next to the Generate button before you submit, and the actual per-call charge is recorded on the prediction afterwards.

What inputs does Flux 2 Klein Base 9b Edit accept?

Key inputs: `prompt`, `images`, `seed`, `enable_base64_output`, `enable_sync_mode`. The full JSON schema (types, defaults, allowed values) is rendered above the Generate button and mirrored in the API reference at https://wavespeed.ai/docs/docs-api/wavespeed-ai/flux-2-klein-base-9b-edit.

How do I get started with the Flux 2 Klein Base 9b Edit API?

Sign up for a free WaveSpeedAI account to claim starter credits, copy your API key from /accesskey, then call the endpoint shown in the API tab of the playground. The playground also auto-generates a code sample in Python, JavaScript, or cURL for the parameters you've set.

Can I use Flux 2 Klein Base 9b Edit outputs commercially?

Commercial usage rights depend on the model's license, set by its provider (WaveSpeedAI). The license summary appears on the model card above; see WaveSpeedAI's Terms of Service for platform-level conditions.

ExamplesView all

Related Models

README

WaveSpeed AI FLUX.2 Klein Base 9B Edit

Why Choose This?

Parameters

How to Use

Example Prompt

Pricing

Billing Rules

Best Use Cases

Pro Tips

Notes

Related Models

Flux 2 Klein Base 9b Edit API — Quick start

Flux 2 Klein Base 9b Edit API — Frequently asked questions