Juggernaut Z Fast by RunDiffusion

The fast 4-step Juggernaut Z release for cheaper, faster image generation.

Juggernaut Z Fast is the speed-focused release of Juggernaut Z. It keeps the cinematic, polished Juggernaut look while targeting 4-step generation for lower latency and lower compute cost. Think of it as the Fast/Turbo-style companion to the full Juggernaut Z release.

This repository hosts the official RunDiffusion Fast release artifacts: Fast safetensors variants and GGUF quantizations. The Diffusers export will be added at the repository root when available.

Why Fast

4-step generation for quick iteration and lower cost
Strong Juggernaut Z visual identity with cinematic lighting and polished composition
Better fit for high-volume workflows where the full model's 25-45 step range is too slow
Useful for previewing, concept passes, product mockups, social content, and fast prompt exploration
Available in full Fast weights, FP16, FP8, and GGUF quantized variants

Recommended Settings

Parameter	Recommendation
Steps	`4`
Workflow	Use a Fast/Turbo-compatible Z-Image workflow
CFG	Start with the workflow default; avoid full-model high-step settings
Use case	Fast previews, lower-cost production passes, text-layout checks, product and portrait exploration

The full Juggernaut Z model is still the better choice when you want slower high-step refinement. Use this Fast release when speed and cost matter.

Files In This Repo

File	Format	Notes
`JuggernautZ_Fast_by_RunDiffusion.safetensors`	safetensors	Original Fast release weights
`Juggernaut_Z_V1_Fast_FP16.safetensors`	safetensors fp16	Half-precision Fast weights
`Juggernaut_Z_V1_Fast_FP8_e4m3fn.safetensors`	safetensors fp8 e4m3fn	Lower VRAM footprint
`Juggernaut_Z_V1_Fast_by_RunDiffusion_q8_0.gguf`	GGUF q8_0	Highest-quality quant
`Juggernaut_Z_V1_Fast_by_RunDiffusion_q6_k.gguf`	GGUF q6_k	Balanced quality and size
`Juggernaut_Z_V1_Fast_by_RunDiffusion_q5_k_m.gguf`	GGUF q5_k_m	Medium quant
`Juggernaut_Z_V1_Fast_by_RunDiffusion_q5_k_s.gguf`	GGUF q5_k_s	Smaller q5 quant
`Juggernaut_Z_V1_Fast_by_RunDiffusion_q4_k_m.gguf`	GGUF q4_k_m	Compact quant
`Juggernaut_Z_V1_Fast_by_RunDiffusion_q4_k_s.gguf`	GGUF q4_k_s	Smallest footprint

Example Gallery

The examples below are pulled from the RunDiffusion asset library for the juggernaut z fast release collection and organized by the categories used during curation.

Click any example image to open the larger CDN version.

Category	Count
People	30
Text generation	12
Art & concept	17
Architecture & interiors	10
Product & branding	9
Nature & travel	4
Food & beverage	3

People

Editorial portraits, fashion, lifestyle, sports, and cinematic character studies.


_{05 - Playful Beauty Makeup Portrait}	_{08 - Floral Dress Park Portrait}	_{18 - Boxer Athlete Portrait}
_{22 - Neon Streetwear Alley Portrait}	_{24 - Red Gown Fern Garden Fashion}	_{26 - Gold Editorial Lounge Fashion}
_{27 - Soft Window Light Portrait}	_{28 - Black And White Menswear Portrait}	_{29 - Glamour Undercut Beauty Portrait}
_{30 - Moody Male Close Up}	_{31 - Neon Runner Activewear}	_{33 - White Lace Beauty Close Up}
_{35 - Tactical Black Outfit Portrait}	_{36 - Friendly Laptop Workspace Portrait}	_{37 - Bohemian Desert Fashion Portrait}
_{38 - Businessman Running Neon City}	_{39 - Library Suit Portrait}	_{40 - Soft Transit Window Portrait}
_{41 - White Sunglasses Fashion Close Up}	_{42 - Neon Hallway Curly Hair Portrait}	_{43 - Quiet Kitchen Texting Portrait}
_{45 - Color Gel Beauty Portrait}	_{47 - Green Light Young Man Portrait}	_{48 - Neon Crowd Phone Portrait}
_{51 - Yellow Metro Fashion Portrait}	_{60 - Grocery Clerk Portrait}	_{61 - Redhead Cafe Portrait}
_{63 - Black And White Fashion Villain Portrait}	_{76 - Armored Bearded Warrior Portrait}	_{79 - Tea House Red Dress Portrait}

Text Generation

Readable typography examples: signs, headlines, apparel text, chalkboards, captions, and brand copy.


_{65 - Typewriter Juggernaut Text}	_{66 - Midnight Diner Neon Sign}	_{67 - Rebel Without A Cause Jacket Text}
_{68 - Aeterna Est Stone Inscription}	_{69 - Future Is Now Newspaper}	_{70 - Unsolved Chalkboard Question}
_{71 - California Surf Club T Shirt}	_{72 - Danger Zone Road Sign}	_{74 - Revolution Graffiti Wall}
_{75 - Astronaut Going Home Caption}	_{77 - RunDiffusion Monitor Ad Copy}	_{85 - Readable Chalkboard Paragraph}

Art & Concept

Fantasy, sci-fi, surreal scenes, illustration tests, creature design, and concept-art style outputs.


_{01 - Rain-Soaked Cinematic Warrior Portrait}	_{07 - Neon Futuristic Building}	_{09 - Ocean Double Exposure Portrait}
_{16 - Fashion Sketch Evening Gown}	_{20 - Armored Fantasy Battle Warrior}	_{21 - Classical Roman Emperor Portrait}
_{53 - Floral Green Statue Portrait}	_{57 - Robot Scarecrow With Birds}	_{58 - Dark Floral Creature Mask}
_{64 - Sketch To Portrait Comparison}	_{73 - Zombie Street Character}	_{78 - Cyborg Face Close Up}
_{80 - Cybernetic Villain Pointing}	_{81 - Cat Chase Market Scene}	_{82 - Ballerina On Asteroid}
_{83 - Teddy Bear Ghost Encounter}	_{84 - Skull Flowers Pocket Watch}

Architecture & Interiors

Modern homes, interiors, classical facades, brutalist structures, and cinematic building studies.


_{02 - Cliffside Glass Ocean House}	_{03 - Brutalist Concrete Tower}	_{04 - Sunlit Minimal Interior Lounge}
_{06 - Classical White Facade}	_{10 - Japanese Courtyard Interior}	_{11 - Cathedral Light Interior}
_{14 - Desert Modern White House}	_{17 - Luxury High Rise Interior}	_{19 - Angular Metal Museum Exterior}
_{23 - Indoor Jungle Lounge}

Product & Branding

Product mockups and brand/logo tests showing how Fast handles commercial-style compositions and text-bearing objects.


_{44 - RunDiffusion Watch Product Shot}	_{46 - RunDiffusion Sneaker Ad}	_{49 - RunDiffusion Skincare Jar}
_{50 - RunDiffusion Smartphone Display}	_{52 - RunDiffusion Whiskey Bottle}	_{54 - RunDiffusion Coffee Bag}
_{56 - RunDiffusion Headphones Product Shot}	_{59 - RunDiffusion Burger Wrapper}	_{62 - RunDiffusion Sunglasses Beach Product}

Nature & Travel

Landscape, travel, outdoor, and environmental examples.


_{13 - Rainforest Dog Portrait}	_{25 - Sunset Field Silhouette}	_{32 - Coastal Cliffs Landscape}
_{55 - Blue Scarf Flower Field Fashion}

Food & Beverage

Food, drinks, cafe, cocktail, and still-life examples.


_{12 - Butterflies Over Morning Coffee}	_{15 - Cocktail Ice Splash}	_{34 - Berry Pancake Stack}

Diffusers

A Fast Diffusers export is planned. When added, it will use the same root-level component layout as RunDiffusion/Juggernaut-Z-Image:

model_index.json
transformer/
text_encoder/
tokenizer/
vae/
scheduler/

Until then, use the standalone Fast .safetensors variants with the workflow that matches your local inference stack, or use the .gguf variants with a GGUF-compatible runtime.

Attribution

Juggernaut Z Fast is built on the Z-Image family and released by Team Juggernaut, with training by KandooAI, published by RunDiffusion.

License & Commercial Use

Juggernaut Z Fast is released under CC BY-NC 4.0:

BY: attribute RunDiffusion / Team Juggernaut / KandooAI when sharing output.
NC: non-commercial use only. You may not use the model, or its outputs in a workflow, for commercial purposes without a license.

You are free to fine-tune, merge, build LoRAs, and otherwise modify the model for non-commercial purposes.

For commercial licensing, custom models, business inquiries, or consultation, contact juggernaut@rundiffusion.com.

Downloads last month: 5

GGUF

Model size

6B params

Architecture

lumina2

Hardware compatibility

4-bit

5-bit

6-bit

8-bit

Model tree for RunDiffusion/Juggernaut-Z-Image-Fast

Base model

Tongyi-MAI/Z-Image

Quantized

(16)

this model

RunDiffusion
/

Juggernaut-Z-Image-Fast