Image Gen · Model Guide · 5 min read

FLUX (Black Forest Labs)

The open-weight image generation family that set the current quality standard — from Apache-licensed to API-only tiers.

Basic Information

FLUX is the image-generation family from Black Forest Labs — the team behind the original Stable Diffusion research. The family spans several tiers: open-weight releases (the fast 'schnell' tier and the higher-quality 'dev' tier) that run locally, and hosted pro-tier models available through APIs. FLUX models are known for excellent prompt adherence, legible text inside images, and realistic anatomy — three historic weak spots of diffusion models.

The open tiers run in ComfyUI, Diffusers, and most major local image tools, and have become the default foundation for community fine-tunes and LoRAs.

Best use cases

• High-quality text-to-image for design drafts, concept art, and illustration
• Image editing and inpainting workflows with precise instruction following
• Local batch generation on a single 12–24 GB GPU (schnell/dev tiers)
• Building custom styles on top of an open foundation (LoRA fine-tunes)

Computational Requirements

Open tiers target consumer GPUs: roughly 8–12 GB for the fast tier and 16–24 GB for the quality tier with sensible memory management; the pro tiers are API-only and need none.

• Quantized community builds run the dev tier on 8–12 GB cards with slower generation.

Commercial license

Split by tier: the schnell tier is Apache 2.0 (fully commercial); the dev tier is licensed for non-commercial use only, with commercial use requiring Black Forest Labs' paid license or API access; pro tiers are commercial API products. This split is the single most important thing to check before building a business on FLUX outputs.