Flux API: How to Generate Images with Flux via API

Flux by Black Forest Labs is one of the top AI image generation models available today, known for exceptional prompt adherence and photorealistic output. Renderful gives developers simple REST API access to Flux Pro, Flux Dev, and Flux LoRA training — all through a single integration with pay-per-generation pricing.
What is Flux?
Flux is a family of text-to-image generation models created by Black Forest Labs, the team behind Stable Diffusion. Flux represents a significant leap forward in image quality, prompt understanding, and text rendering capabilities compared to previous generation models.
The Flux family includes Flux Pro for production-grade, highest-quality image generation; Flux Dev for faster iterations during development and prototyping; and LoRA fine-tuning support that lets you train custom models on your own images for consistent styles, characters, or product visuals.
How to Use the Flux API
With Renderful, generating images with Flux is a single API call. Sign up for an API key, then send a POST request with your prompt and model selection. Here's a working example:
curl -X POST https://api.renderful.ai/api/v1/generations \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "flux/flux-pro",
"input": {
"prompt": "A majestic snow leopard resting on a rocky mountain ledge at golden hour, photorealistic",
"width": 1024,
"height": 1024
},
"webhook": "https://your-app.com/webhook"
}'The API is asynchronous — your webhook will receive the completed image once generation finishes. You can also poll the generation status endpoint for progress updates.
Flux Models Available
Renderful provides access to the full range of Flux model variants through a single API:
| Model | Description | Best For |
|---|---|---|
| Flux Pro | Highest quality, production-grade image generation | Production apps |
| Flux Dev | Faster generation with slightly reduced quality | Prototyping |
| Flux LoRA | Fine-tuned models trained on custom datasets | Custom styles |
Flux API Pricing
Renderful offers competitive pay-per-generation pricing for Flux API access with no monthly minimums or commitments:
| Feature | Renderful |
|---|---|
| Pricing Model | Pay-per-generation |
| Starting Price | From ~$0.03 / image |
| Monthly Minimum | None |
| Free Credits | Yes, on sign up |
| Models Included | Flux Pro, Dev, LoRA + 20 more |
Why Use Renderful for Flux API
Renderful is the easiest way to integrate Flux into your application. Here's what you get:
Unified API for 20+ Models
One integration gives you access to Flux Pro, Flux Dev, Stable Diffusion, DALL-E, and more. Switch between models by changing a single parameter.
LoRA Fine-Tuning
Train custom Flux LoRA models on your own images through the API. Generate consistent brand visuals, characters, or product shots at scale.
Webhook Support
Receive completed generations via webhook callbacks. No need to poll for results or manage long-running connections.
Competitive Pricing
Pay only for what you generate starting at ~$0.03 per image. No monthly subscriptions or upfront commitments.
Python & JavaScript SDKs
Get started quickly with official SDKs for Python and JavaScript/TypeScript. Or use the REST API directly with cURL.
Frequently Asked Questions
What is the Flux API?
How much does Flux API cost?
What Flux models are available?
Can I train custom LoRA models with the Flux API?
Is Flux better than Stable Diffusion?
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Start Using Flux API Today
Create your Renderful account, get free credits, and start generating images with Flux Pro, Flux Dev, and 20+ other AI models through a single API.