FLUX.2 [klein] (4B / 9B)
Snapshots flux-2-klein-9b (fixed) and flux-2-klein-9b-preview (latest, KV caching). HF also hosts -base, fp8 and nvfp4 variants. Release date = HF repo creation date.
- Input
- text, image
- Output
- image
- License
- apache-2.0 (4B); FLUX Non-Commercial License (9B)
- Pricing
- per image: $0.014 (per image from (4B; 9B from 0.015; text-to-image and editing)) source
- Verified
- 2026-09-29
How to call it
| Provider | Model id | Endpoint / URL | Docs |
|---|---|---|---|
| BFL API | flux-2-klein-4b | https://api.bfl.ai/v1/flux-2-klein-4b | docs |
| BFL API | flux-2-klein-9b | https://api.bfl.ai/v1/flux-2-klein-9b | docs |
| Hugging Face | — | huggingface.co/black-forest-labs/FLUX.2-klein-4B | — |
| Hugging Face | — | huggingface.co/black-forest-labs/FLUX.2-klein-9B | — |
Notable capabilities (3)
- Sub-second generation and editing: Size-distilled FLUX.2 variants aimed at sub-second inference for both text-to-image and editing. source
- Apache-2.0 open weights (4B): 4B checkpoint is Apache 2.0 - commercially usable open weights; base (undistilled) checkpoints published for fine-tuning/LoRA training. source
- KV-cached 9B variant (found after launch): flux-2-klein-9b-preview / FLUX.2-klein-9b-kv (Mar 2026) add KV caching for faster multi-reference editing. source
Small, fast FLUX.2 models for real-time/local use; 4B is Apache-2.0.
curl -X POST https://api.bfl.ai/v1/flux-2-klein-4b -H "x-key: $BFL_API_KEY" -H "Content-Type: application/json" -d '{"prompt":"minimal poster, the word KLEIN in bold red"}'
Local: diffusers with black-forest-labs/FLUX.2-klein-4B.
Sources: https://docs.bfl.ai/flux_2/flux2_overview , https://docs.bfl.ai/quick_start/pricing , https://huggingface.co/black-forest-labs
Other Black Forest Labs models
FLUX.2 [max] · FLUX.2 [dev] · FLUX.2 [pro] · FLUX 3 · FLUX.1 Kontext [pro] / [max]