FLUX.1.
The photorealism frontier — built by the Stable Diffusion founders, now powering xAI Grok.
What it is.
Black Forest Labs is the Freiburg studio founded in 2024 by the founding team and the original Stable Diffusion team. FLUX.1 ships in three tiers: schnell for speed, dev for tuning, pro for fidelity. xAI selected FLUX to power Grok image generation. Distributed via API and via partners including Replicate, Together, and fal.
Where it fits.
Where photorealism matters more than stylisation. Editorial photo desks replacing stock libraries. Product teams generating catalogue imagery against SKU lists they cannot afford to shoot. Anywhere the operator wants European data-governance posture without ceding control to a hyperscaler.
- Best photorealism among open-weights image models
- Open dev weights enable on-prem deployment
- Powers xAI Grok and a growing API tier
- Smaller community than Stable Diffusion ecosystem
- Pro tier pricing climbs fast at production volume
Frequently asked.
Are FLUX.1 weights open?
FLUX.1 dev and schnell ship under open licences. FLUX.1 pro is API-only. Commercial use of dev requires a paid licence above a revenue threshold.
Why did xAI pick FLUX over Stable Diffusion?
FLUX leads on photorealism and prompt adherence. The Black Forest founders built both — xAI hired the newer model.
Can FLUX run on a single GPU?
Yes. FLUX.1 dev runs on a 24GB consumer card. Schnell runs on 16GB. Pro runs only on the hosted API.
The open-weights image model — the foundation of the entire generative-art ecosystem.
The image-model reference point — still the aesthetic benchmark in 2026.
The text-in-image model — the production reference for typography that actually renders.