Fast Checker Pattern [LP]

You've seen this pattern a thousand times - it's the gray-and-white checkerboard every image editor uses to represent transparency. This node generates one on demand, sized and colored however you want, so you have something to put behind an image with a transparent background to actually check whether the transparency looks right.

Why you'd generate this instead of just eyeballing a PNG

A transparent PNG viewed against a plain white or black background can hide real problems - a soft edge that's semi-transparent when it should be crisp, a halo of the wrong color left over from a bad cutout, alpha that's inverted. Viewing it against a checker pattern instead makes those issues visible immediately, the same reason Photoshop and every other editor defaults to this exact pattern for transparent layers. The README is explicit that this node only generates the background: "you need to combine the resulting background image with your image with a transparent background in other ComfyUI nodes" - an image composite/overlay step afterward, not something this node does for you.

The inputs and outputs that matter

• width / height - the generated image's size, default 512×512, range 64–4096.
• color_1 / color_2 - the two checker colors, picked from a dropdown of about 30 named presets (white, black, red, blue, and so on) plus a custom option.
• grid_frequency - an INT, default 50, range 1–200, controlling how many squares tile across the pattern. Higher values mean more, smaller squares - this sets a count, not a fixed pixel size, so the visual density of squares scales with your width/height choice.
• color1_hex / color2_hex - optional STRING fields (defaulting to #C0C0C0 and #808080) that only matter when color_1/color_2 is set to custom. Worth noting: those defaults are the exact silver/gray pair most image editors use for their own transparency checker, so leaving custom selected with the defaults untouched reproduces the familiar look.
• Output - a single IMAGE.

How to install it

ComfyUI Manager: search "ComfyUI Level Pixel" or ComfyUI-LevelPixel, install, restart - updates automatically via Manager's "Update ALL." Manual:

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

Restart ComfyUI. No models, nothing else needed - it's generated procedurally.

Common issues & troubleshooting

You picked a color from the dropdown but the hex fields don't seem to do anything. That's expected - color1_hex/color2_hex only take effect when the corresponding color_1/color_2 dropdown is set to custom. Picking a named preset like red ignores the hex field entirely.

The checker squares look too big or too small for what you wanted. Adjust grid_frequency, not width/height - frequency controls how many squares tile across the image, so raising it shrinks each square without changing the overall canvas size.

The transparent image still doesn't composite onto this correctly. This node only produces the background - it doesn't know anything about your transparent image or do any compositing itself. You still need an image-overlay or composite node afterward (this pack's own Image Overlay node is one option) to actually lay your transparent PNG on top of the pattern this generates.