ComfyUI Auto Size

A ComfyUI custom node for handling image resolutions with smart, model-aware presets for 2026 diffusion models.

🌟 Supported Models

Model	Use Case	Resolution Multiple	Source
Qwen-Image	Text-image-to-image	28px	Official docs
Illustrious	Anime	32px	Community standard
Z-Image	Text-image-to-image	32px	Official docs
Flux2-Klein/Flux	Text-image-to-image	32px	Similar to Z-Image/Illustrious

✨ Features

• Dynamic Dropdowns: Size dropdown filters to show only relevant presets for your selected model
• Model-Aware Snapping: Automatically rounds resolutions to required multiples (28px or 32px)
• Robust Resizing: Multiple resize modes—Center Crop, Scale to Fit, Stretch to Fill

📦 Nodes

Auto Size Latent

Category: latent/AutoSize

Generates an empty latent tensor at a model-aligned resolution.

Input	Description
model	Target model (qwen-image, z-image, flux, illustrious)
size	Preset or "Full Custom"
custom_longer_size	Longer side in pixels (set to 0 to use preset)
custom_ratio	Aspect ratio for custom mode
batch_size	Number of latents

Outputs: latent, width, height, size

Auto Size (Image/Mask)

Category: image/AutoSize

Resizes an existing image and/or mask to target dimensions.

Input	Description
crop_method	Center Crop, Top-Left Crop, Scale to Fit, Stretch to Fill
scale_method	lanczos, bicubic, bilinear, nearest
image	Optional input image
mask	Optional input mask

Outputs: image, mask, width, height, size

🛠️ Installation

cd ComfyUI/custom_nodes
git clone https://github.com/jluo-github/comfyui-auto-size.git

Restart ComfyUI and reload the browser.

⚙️ Resolution Logic

1. Custom Override (custom_longer_size > 0): Calculates resolution from longer side + ratio, snapped to model's multiple
2. Preset Mode (custom_longer_size = 0): Uses the Size dropdown value directly

� Project Structure

nodes/     ComfyUI node definitions
utils/     Core logic (presets, resizing)
js/        Dynamic dropdown behavior
tests/     Unit tests

License

MIT License

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Made with ❤️ for the ComfyUI community