FLUX.2 [klein] AIO

SeeSeeLP

219

flux.2 ultra-fast image editing text-to-image all-in-one nvfp4 fp16 bf16 fp8 klein aio base model

Flux.2-4B-Distilled-AIO

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About this version

🚀 FLUX.2 [klein] 4B AIO | Sub-Second Image Generation

Ultra-Fast • 4-6 Steps • Text-to-Image + Image Editing • All-in-One • Apache 2.0

✨ What is FLUX.2 [klein] 4B AIO?

FLUX.2 [klein] 4B AIO is an All-in-One repackage of Black Forest Labs' newest compact image generation model. This version includes VAE, Text Encoder (Qwen3) and UNet in a single file – just load and go!

"Klein" means "small" in German – but this model is anything but limited. It delivers exceptional performance in Text-to-Image, Image Editing and Multi-Reference Generation, typically reserved for much larger models.

📦 Available Versions

🟡 FP8-AIO (~7.7 GB) – Recommended for most users

Precision: FP8
UNet: FP8
Text Encoder: FP8
VAE: BF16
Best for: Most users, quick tests, everyday use, lowest VRAM

🔵 FP16-AIO (~15 GB) – For older GPUs

Precision: FP16
UNet: FP16
Text Encoder: FP16
VAE: BF16
Best for: Older GPUs (GTX 10xx, RTX 20xx), broadest compatibility

🟢 BF16-AIO (~15 GB) – Maximum quality

Precision: BF16
UNet: BF16
Text Encoder: BF16
VAE: BF16
Best for: RTX 30xx/40xx/50xx, professional/commercial work

🎯 Key Features

⚡ 4-6 Step Generation – Sub-second inference on modern hardware
📦 All-in-One – No separate VAE/Text Encoder download needed
🎨 Unified Architecture – T2I, I2I Editing & Multi-Reference in one model
📐 1024×1024 native – Optimized for this resolution
💾 Low VRAM – Runs on consumer GPUs with ease
📜 Apache 2.0 – Fully open for commercial use!
🔧 LoRA-compatible – Base version ideal for fine-tuning

⚙️ Recommended Settings

Steps: 4-6 (step-distilled, more steps ≠ better)
CFG: 1.0 ⚠️ CRITICAL!
Sampler: euler
Scheduler: simple (or "normal")
Resolution: 1024×1024 (native)

⚠️ CRITICAL: CFG Must Be 1.0!

This is a distilled model optimized for CFG 1.0. Higher CFG values will produce worse results!

✅ CFG 1.0 = Correct
❌ CFG 3.5+ = Wrong, will look bad

Additional Notes

4-6 Steps are optimal! The model was step-distilled for fast inference
No negative prompts needed – works but not required
Natural language prompts – Just describe what you want to see

📥 Installation (ComfyUI)

Quick Start

Download your preferred version (FP8/FP16/BF16)
Place in ComfyUI/models/checkpoints/
Load with the "Load Checkpoint" node
Generate!

Folder Structure

ComfyUI/
└── models/
    └── checkpoints/
        └── flux-2-klein-4b-bf16-aio.safetensors  (or fp16/fp8)

🎨 Example Prompts

Photorealistic

A professional photograph of a barista making latte art in a cozy 
coffee shop, morning light streaming through windows, shallow depth 
of field, shot on Sony A7III

Digital Art

A majestic dragon perched on a crystal mountain peak, aurora borealis 
in the background, fantasy digital painting, highly detailed scales, 
dramatic lighting

Product Photography

Minimalist product photo of a luxury perfume bottle on white marble, 
studio lighting, reflection, commercial photography

💻 Capabilities

✅ What FLUX.2 [klein] 4B can do:

Text-to-Image (T2I) – High-quality image generation from text
Image-to-Image (I2I) – Single-reference editing
Multi-Reference – Multiple input images for controlled transformations
Text Rendering – Improved text rendering in images
Photorealistic – Professional photo quality
Artistic Styles – Diverse artistic styles

⚠️ Limitations:

Optimized for 1024×1024 (other resolutions possible but not optimal)
4B model – less detail than larger models for complex scenes
Distilled version – less output diversity than base models

🔧 Technical Details

Parameters: 4 Billion
Architecture: Rectified Flow Transformer
Text Encoder: Qwen3-based
Inference Steps: 4-6 (step-distilled)
Native Resolution: 1024×1024
Precision: BF16 / FP16 / FP8
License: Apache 2.0

🆚 Comparison: 4B vs 9B

FLUX.2 [klein] 4B

Parameters: 4B
VRAM: ~8-13 GB
GPU: RTX 3090/4070+
Quality: Very Good
License: Apache 2.0 ✅
Commercial Use: Yes!

FLUX.2 [klein] 9B

Parameters: 9B
VRAM: ~29 GB
GPU: RTX 4090+
Quality: Excellent
License: Non-Commercial ❌
Commercial Use: No

→ 4B is perfect for: Consumer hardware, commercial projects, fast iterations

❓ FAQ

Q: Do I need separate VAE/Text Encoder files?

No! AIO = All-in-One. Everything is included in a single file.

Q: Can I use this for commercial projects?

Yes! The 4B version is licensed under Apache 2.0.

Q: Why only 4-6 steps?

The model was step-distilled. More steps won't improve quality.

Q: Why must CFG be 1.0?

This is a distilled model optimized for CFG 1.0. Higher values will degrade output quality.

Q: FP8 vs BF16 – What's the difference?

FP8 is smaller and faster, BF16 has slightly better quality. For most applications FP8 is sufficient.

Q: Does this work with LoRAs?

Yes! Especially the Base version (non-distilled) is ideal for LoRA training.

Q: What's the difference to the 9B version?

9B has better quality but is non-commercial only. 4B is Apache 2.0!

🐛 Troubleshooting

Images look "washed out" or oversaturated

Check CFG – must be 1.0 for distilled model!
Use 4-6 steps

Poor text rendering

Be more specific in your prompt
Use simple, short text
Place text requirements at the beginning of the prompt

Colors look off

Try BF16 version instead of FP8
Ensure your monitor is properly calibrated

🙏 Credits

Original Model: Black Forest Labs Architecture: Rectified Flow Transformer Text Encoder: Qwen3 AIO Repackage: SeeSee21

Official Links:

📋 Changelog

v1.0 (January 2026)

Initial Release
BF16, FP16 and FP8 versions
All-in-One with VAE + Text Encoder + UNet

License: Apache 2.0 – Free for personal AND commercial use! 🎉

The fastest open-source image generation model for ComfyUI! ⚡

Download and start creating! 🚀

Model description