FLUX.2 [klein] 4B is a compact 4-billion-parameter text-to-image model that delivers fast generation with quality results. Ready-to-use REST inference API, best performance, no cold starts, affordable pricing.
Bezczynny

$0.008za uruchomienie·~125 / $1

ancient monumental Teotihuacán pyramids illuminated by red lights, in the sky a giant Saturn suspended in the sky, sculptural and non-astronomical, with rings of liquid metal, futuristic yet archaic, evoking a sacred portal rather than a planet, little light fog, cinematic depth and atmospheric perspective, minimal composition with large clean negative space for typography

Black and white photo of New York City, skate culture aesthetic, strong focus on tall buildings and urban architecture, low angle perspective, gritty street vibe, raw and authentic mood, high contrast, grainy film photography, underground skate scene feeling, cinematic composition, moody lighting, urban attitude

A man with a sleek, sculpted face, dressed in a matte burgundy velvet suit. A large velvet-textured black panther (wine tint) sitting beside him. Editorial, dramatic, ultra-premium light.

a skeleton surfing while drinking a beer in a cartoonish style, large resolution and high quality, on a black background

A beautiful girl, 29-35 years old, European-looking, kind, spontaneous, smiling, with long, thick, loose chestnut-colored hair (the hair has a slight reddish tint in the sun), riding a horse, in nature, a sandy landscape, the ocean is visible, and the girl and horse are visible in full growth, 85 mm lens, cinematic lighting, skin with pores and microtexture.
FLUX.2 Klein 4B Text-to-Image is a lightweight yet capable text-to-image generation model. Describe your vision in text and get quality images with fast generation — the most affordable option in the FLUX.2 Klein family.
Fast and affordable 4B parameter model optimized for quick turnaround at the lowest cost in the Klein series.
Good prompt adherence Accurately interprets prompts to generate images that match your description.
Flexible sizing Custom width and height controls for any aspect ratio.
Prompt Enhancer Built-in tool to automatically improve your prompts for better results.
Best value Ideal for rapid prototyping, batch processing, and budget-conscious projects.
| Parameter | Required | Description |
|---|---|---|
| prompt | Yes | Text description of the image you want to generate |
| width | No | Output width in pixels (default: 1024) |
| height | No | Output height in pixels (default: 1024) |
| seed | No | Random seed for reproducibility (-1 for random) |
| Item | Cost |
|---|---|
| Per image | $0.008 |
Simple flat-rate pricing regardless of image size.
Grab a WaveSpeedAI API key, then call POST https://api.wavespeed.ai/api/v3/wavespeed-ai/flux-2-klein-4b/text-to-image 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 4b Text To Image below.
# Submit the prediction
curl -X POST "https://api.wavespeed.ai/api/v3/wavespeed-ai/flux-2-klein-4b/text-to-image" \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $WAVESPEED_API_KEY" \
-d '{
"prompt": "A cinematic shot of a city at sunset, soft golden light",
"size": "1024*1024",
"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].// 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-4b/text-to-image", {
"prompt": "A cinematic shot of a city at sunset, soft golden light",
"size": "1024*1024",
"seed": -1,
"enable_sync_mode": false,
"enable_base64_output": false
});
console.log(result.outputs[0]); // → URL of the generated output# pip install wavespeed
import wavespeed
output = wavespeed.run(
"wavespeed-ai/flux-2-klein-4b/text-to-image",
{
"prompt": "A cinematic shot of a city at sunset, soft golden light",
"size": "1024*1024",
"seed": -1,
"enable_sync_mode": false,
"enable_base64_output": false
}
)
print(output["outputs"][0]) # → URL of the generated outputFlux 2 Klein 4b Text To Image is a WaveSpeedAI model for image generation, exposed as a REST API on WaveSpeedAI. FLUX.2 [klein] 4B is a compact 4-billion-parameter text-to-image model that delivers fast generation with quality results. 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.
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-4b-text-to-image.
Flux 2 Klein 4b Text To Image starts at $0.008 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.
Key inputs: `prompt`, `size`, `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-4b-text-to-image.
Average end-to-end generation time on WaveSpeedAI is around 10 seconds per request — measured across recent runs. Queue time scales with global demand; live status is visible in the prediction record.
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.