Curiosity · AI Model

Black Forest Labs FLUX.1 [dev]

FLUX.1 [dev] is the open-weight sibling of FLUX.1 [pro] — a 12-billion-parameter diffusion transformer released under a non-commercial research licence. It delivers near-[pro] quality on a single prosumer GPU and anchors the community LoRA ecosystem around FLUX.

Model specs

Vendor
Black Forest Labs
Family
FLUX.1
Released
2024-08
Context window
1 tokens
Modalities
text, vision

Strengths

  • Near-[pro] quality with open weights
  • Runs on 24 GB GPUs (FP16) or 12 GB with quantisation
  • Active community — LoRAs, ControlNets, and IP-Adapters
  • Transparent architecture for research

Limitations

  • Non-commercial research licence — cannot sell outputs without a separate deal
  • Slightly behind [pro] on photorealism
  • No token context — cost is compute, not tokens
  • Requires self-hosted GPU infrastructure

Use cases

  • Self-hosted research and experimentation
  • Community LoRA training for characters and styles
  • Offline creative pipelines in ComfyUI
  • Fine-tuning and distillation experiments

Benchmarks

BenchmarkScoreAs of
GenEval composition≈0.742024-08
Human preference vs SDXL≈70% win-rate2024-08

Frequently asked questions

What is FLUX.1 [dev]?

FLUX.1 [dev] is the open-weight, research-licensed version of Black Forest Labs' 12-billion-parameter FLUX text-to-image diffusion transformer. It is the standard base model for the FLUX community LoRA ecosystem.

Can I use FLUX.1 [dev] commercially?

Not under the default non-commercial licence. For commercial use, either purchase a licence from Black Forest Labs or use FLUX.1 [pro] / [schnell] (schnell is Apache-licensed) depending on your quality and cost needs.

What hardware do I need for FLUX.1 [dev]?

A single 24 GB GPU runs FP16 comfortably. With 8-bit or GGUF quantisation the model fits on 12–16 GB consumer GPUs, albeit with some quality or speed trade-off.

How does it compare with Stable Diffusion 3.5?

FLUX.1 [dev] generally leads on photorealism and prompt adherence, while SD 3.5 benefits from a larger LoRA and ControlNet ecosystem plus a commercial community licence. Pick based on whether quality or ecosystem breadth matters more.

Sources

  1. Black Forest Labs — FLUX.1 announcement — accessed 2026-04-20
  2. Hugging Face — black-forest-labs/FLUX.1-dev — accessed 2026-04-20