Ceil

Ceil is math.ceil() wearing a node's clothes. Feed it a number, get back the smallest integer that's greater than or equal to it - 3.1 becomes 4, -3.1 becomes -3, 4.0 stays 4. If that sentence told you everything you needed, go wire it up and skip the rest.

Where it actually earns a spot: ComfyUI is full of places that compute a size, a ratio, or an offset as a float and then hand it to something that insists on an integer - an image width, a batch count, a crop coordinate. Divide two dimensions or multiply by a scale factor and you've got a float that needs rounding before the next node will even accept the wire. Ceil is the "round toward more" half of that job; its sibling Floor (same pack) rounds toward less.

How it works

It's math.ceil(input1), nothing fancier. No clamping, no bounds checking, no special-casing for negatives - they round up toward zero the same way math.ceil always has.

The inputs and outputs that matter

One input, one output, whole node:

• input1 - typed * in the schema, meaning it takes anything wired in. In practice that's an INT or FLOAT coming from upstream math; there's no default shown because it's meant to be fed, not typed by hand.
• Output - INT, always. Even a value that's already whole comes out as INT, so this doubles as a float-to-int converter when you need one.

How to install it

Grab the whole pack - Ceil doesn't ship alone. In ComfyUI Manager, search ComfyUI-LogicUtils, install, restart. Or by hand:

cd ComfyUI/custom_nodes
git clone https://github.com/aria1th/ComfyUI-LogicUtils

then restart. No models, no meaningful dependencies - it's plain Python, so once the folder's in place and ComfyUI has restarted, you're done.

Worth knowing going in: the author is aria1th, better known as AngelBottomless, the trainer behind Illustrious XL - the anime SDXL finetune that displaced Pony Diffusion v6 as the open-source default. LogicUtils is a side project, a grab-bag of small utility nodes he wrote for his own graphs, and the README says exactly where the docs stand: "Proper documentation is being prepared, however there are too many nodes." That's been true since the repo went quiet in early 2026, around when his public work moved away from image generation entirely. It's a real, working pack people build workflows on - it just doesn't explain itself, which is what this article is for.

Common issues & troubleshooting

The node's missing or greyed out after install. Check the folder under custom_nodes is named exactly ComfyUI-LogicUtils - a manual zip download sometimes appends -main - then do a full restart, not just a browser refresh.

A negative number "rounded the wrong way." It didn't. math.ceil(-3.7) is -3, not -4 - ceiling always means toward positive infinity, never toward zero.

You actually wanted nearest, not always-up. Ceil only rounds up. For nearest, do the comparison yourself with this pack's Min/Max nodes, or just reach for Floor if "down" happens to be closer to what you want.