Image Dimensions (Multiple of 16)

Image Dimensions (Multiple of 16) is a pass-through node with training wheels: it takes width, height, and a frame count, and hands them back unchanged - but the sliders are locked so you can't pick values that break video models. Width and height step by 16, and the third input, length, defaults to 81 with the author's own tooltip: "Length for WanVace."

That's the whole story. This node exists for Wan workflows, and specifically the Wan 2.1 VACE (video editing) pipeline, where resolutions that aren't multiples of 16 and frame counts that aren't in the 4n+1 family cause silent problems or outright errors. 832x480 with 81 frames is the Wan 2.1 standard combo - the modidex Wan notes list 480p and 720p as the reference outputs, with 81 frames as the canonical clip length.

The inputs

• width (INT, 16–16384, step 16, default 832)
• height (INT, 16–16384, step 16, default 480)
• length (INT, step 4, default 81) - the frame count, stepped by 4 so you land on the 4n+1 family (81, 85, 89...) Wan expects.

Outputs: width, height, length as INTs. Wire them into EmptyLatentImage, a Wan sampler, or anything else that takes explicit dimensions.

How it works, and what it doesn't do

Mechanically it returns the inputs verbatim. The value is the constraint, not the computation: the step-16 and step-4 sliders keep your numbers in the valid range by construction. What it is not is a calculator - it won't snap a random width to the nearest multiple of 16, and it won't derive height from an aspect ratio. If you feed it 900, the slider lands on 896 or 912 and that's your answer, but you're doing the snapping. For auto aspect-ratio math you'd want a different node entirely.

Why the defaults are what they are

The pack's other Wan-ish node, Resolution Wan, shares the same 832x480 default - that's the 16:9-ish 480p shape Wan was tuned around. If you're building a Wan 2.1 graph from scratch, these defaults are a sane starting point and the length slider keeps your frame count legal. If you're not doing video at all, this node is pointless - a plain integer node does the same pass-through without the constraint, and for images a step-8 or free slider is fine.

Installation

From Praveen's ComfyUI Tools. Install via ComfyUI Manager (search "Praveen" / "praveen-tools"), or:

cd ComfyUI/custom_nodes
git clone https://github.com/Praveenhalder/praveen-tools

Restart ComfyUI. No extra dependencies, no model downloads. It's a small utility in a small pack - grab it if you live in Wan workflows and want one less thing to keep straight.