What is FLUX?
FLUX is the image generation model family developed by Black Forest Labs, founded by the original creators of Stable Diffusion. Released in August 2024, FLUX.1 immediately established itself as the strongest open-weight model available, producing images that rival Midjourney V6 in quality while remaining accessible for self-hosting.
The FLUX family includes three variants: FLUX.1 pro (closed API only), FLUX.1 dev (open weights for research and non-commercial use), and FLUX.1 schnell (Apache 2.0 licensed for commercial use). This tiered approach allows developers to experiment freely while offering a premium API for production use cases.
FLUX excels particularly at photorealism and natural human portraits, areas where previous open-source models had struggled. Its architecture uses a hybrid transformer approach that handles long prompt descriptions more effectively than traditional diffusion models. It has rapidly become the preferred base model for fine-tuning in the open-source community.
Key Features
- Three model tiers: pro API, dev research, schnell commercial
- State-of-the-art photorealism and portrait quality
- Superior long prompt comprehension
- Hybrid transformer architecture using Flow Matching
- Available on Hugging Face, Replicate, and fal.ai
- LoRA training support via community tools
- Fast inference with schnell variant in 1-4 steps
- FLUX.1 dev open weights for research use
- Improved text rendering over previous open models
- Growing fine-tune ecosystem on Civitai
Pros & Cons
Pros
- Image quality matches or exceeds Midjourney on many prompts
- Open-weight dev and schnell models available for self-hosting
- Excellent at natural human portraits and photorealism
- Apache 2.0 schnell model for commercial use at no cost
Cons
- Pro model only accessible via paid API
- Dev model restricted to non-commercial research use
- Fewer fine-tunes and LoRAs compared to SD ecosystem
- Higher compute requirements than older SD models
Pricing
Model: Freemium
| Plan | Price | Key Limits |
|---|---|---|
| FLUX.1 schnell self-hosted | $0 | Free, Apache 2.0 commercial license |
| FLUX.1 dev self-hosted | $0 | Free for non-commercial research only |
| FLUX.1 pro via API | Pay-per-use | Approximately $0.055 per image on Replicate or fal.ai |
| BFL API | Pay-per-use | Direct API from Black Forest Labs, variable pricing |
FAQ
- Is FLUX free to use?
- FLUX.1 schnell is free under Apache 2.0 for commercial use when self-hosted. FLUX.1 dev is free for non-commercial research. The pro variant requires API payment.
- Does FLUX have an affiliate program?
- Black Forest Labs does not currently offer an affiliate program. Third-party platforms hosting FLUX may have their own programs.
- FLUX vs Stable Diffusion: which is better?
- FLUX produces significantly better quality images out of the box, especially for photorealism. Stable Diffusion has a much larger ecosystem of fine-tunes and tools accumulated over several years.
- Where can I try FLUX online without installing anything?
- FLUX is available on Hugging Face Spaces, fal.ai, Replicate, and Freepik Mystic. Several platforms offer free credits to try it.
- Can I fine-tune FLUX on my own images?
- Yes. FLUX.1 dev can be fine-tuned with LoRA using tools like SimpleTuner. The schnell model is also fine-tunable for commercial use under its Apache 2.0 license.