YepAPI
Black Forest LabsImage Generation/v1/media/queue

FLUX 3 Image Klein API

FLUX 3 Image Klein from $0.02 per image — open-weights FLUX 3 generation and editing, no GPU to rent.

The open-weights FLUX 3 tier. Low-cost text-to-image and reference editing that keeps characters and subjects consistent — from $0.02 per image.

No credit card required. Takes 30 seconds.

FLUX 3 Image Klein API pricing

Pay per request from your YepAPI balance — no subscription, no monthly minimum. Prices updated October 23, 2026.

BillingPrice
Rate$0.02/image
What it costsPer job
1 imagefrom default size$0.02
100 imagesa product catalog batch$2.00
1,000 imagesa month of app traffic$20.00

2,400+

Developers

1.2M+

API calls served

100+

Endpoints

$0.01

Per call

Yep, that's it.

Try it live

Enter a prompt and generate an image with FLUX 3 Image Klein.

POST/v1/media/queue

Drop image or click to upload

For image-to-image editing

Response
Hit "Send Request" to see the response

FLUX 3 Image Klein specs

ProviderBlack Forest Labs
Model IDblack-forest-labs/flux-3-image-klein
Endpoint/v1/media/queue
TypeImage Generation
Output formatsjpeg
Image inputYes

How to get a FLUX 3 Image Klein API key

  1. 1

    Create a free account

    Sign up at yepapi.com with Google or email. It takes about 30 seconds and needs no card.

  2. 2

    Create an API key

    Open the dashboard, go to API Keys and create a key. Copy it — it starts with yep_sk_.

  3. 3

    Call FLUX 3 Image Klein

    Send a request to /v1/media/queue with the x-api-key header and model "black-forest-labs/flux-3-image-klein".

  4. 4

    Pay as you go

    Usage is billed per request from your balance. Top up any amount; there is no subscription.

Strengths

✓
Open-weights FLUX 3

FLUX 3 Image Klein is the open-weights member of the FLUX 3 family.

✓
Consistent subjects

Suited to reference-based editing that keeps characters and subjects consistent across a set of images.

✓
From $0.02 per image

The lowest-priced FLUX 3 tier, practical for drafts and high-volume generation.

✓
Same family as FLUX 3 Image

Prompts move to the flagship FLUX 3 Image model when a draft needs a final render.

Quick start

Copy this snippet and start making calls with FLUX 3 Image Klein.

// Step 1: Submit job
const res = await fetch('https://api.yepapi.com/v1/media/queue', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "model": "black-forest-labs/flux-3-image-klein",
    "prompt": "A red fox in a knitted scarf reading a map on a mossy tree stump, children's book illustration, soft watercolor textures, warm autumn palette",
    "options": {
      "aspectRatio": "1:1"
    }
  }),
});
const { data } = await res.json();
const jobId = data.jobId;

// Step 2: Poll for result
const status = await fetch(`https://api.yepapi.com/v1/media/status/${jobId}`, {
  headers: { 'x-api-key': 'YOUR_API_KEY' },
});
const { data: job } = await status.json();
// job.status: "pending" | "processing" | "completed" | "failed"
// job.result: { text?, image?, audio?, video? }

FLUX 3 Image Klein vs similar models

Every model below runs on the same API key — switch by changing the model ID.

ModelProviderPrice
FLUX 3 Image KleinBlack Forest Labsfrom $0.02/image
FLUX.2 KleinBlack Forest Labsfrom $0.03/image
FLUX.2 ProBlack Forest Labsfrom $0.07/image
FLUX.2 FlexBlack Forest Labsfrom $0.11/image
FLUX 3 ImageBlack Forest Labsfrom $0.11/image
FLUX.2 MaxBlack Forest Labsfrom $0.15/image
GPT Image 2OpenAIfrom $0.02/image
GPT Image 1 MiniOpenAIfrom $0.02/image

Why use FLUX 3 Image Klein through YepAPI?

✓One API key for all models — no separate accounts
✓No monthly minimums — pay per call
✓Switch models with one line of code
✓Simple REST API — works from any language
✓Unified billing across all providers
✓No rate limits for most use cases

FLUX 3 Image Klein API — open-weights FLUX 3 from $0.02

FLUX 3 Image Klein is an open-weights image generation and editing model from Black Forest Labs. It is suited to text-to-image work and to reference-based editing that keeps characters and subjects consistent across images.

On YepAPI you call it on `/v1/media/queue` at about $0.02 per image, with JPEG output by default — no self-hosting, no GPU provisioning, and the same key as the rest of the catalog.

Start generating in 30 seconds

$5 free credit on signup. No credit card required. Pay per call.

What developers say

“Switched from SerpAPI and cut our SERP costs by 80%. Same data quality, way simpler billing.”

Marcus T.

SEO Platform Founder

“One API key for AI models, SERP data, and web scraping. Saved us from managing 4 separate providers.”

Priya S.

Full-Stack Developer

“The $5 free credit let us prototype our entire rank tracking feature before committing. No other API does that.”

Jake R.

Indie Hacker

Frequently asked questions

The open-weights FLUX 3 tier. Low-cost text-to-image and reference editing that keeps characters and subjects consistent — from $0.02 per image.

FLUX 3 Image Klein costs from $0.02/image through YepAPI, billed per request with no monthly fee. For example, a 1 image (from default size) costs about $0.02.

Sign up at yepapi.com (Google or email, about 30 seconds), open the dashboard and create an API key. The same key works for FLUX 3 Image Klein and every other model — no separate Black Forest Labs account or waitlist.

New YepAPI accounts in most countries get free signup credit, enough to test FLUX 3 Image Klein without a card. After that you pay per request at the rates above — there is no subscription.

Use "black-forest-labs/flux-3-image-klein" as the model on /v1/media/queue. The short alias "flux-3-klein" also works.

Ready to use FLUX 3 Image Klein?

$5 free credit on signup. No credit card required. Pay per call.

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