Resolution Multiply (JPS)

This is a one-job node: take a width and height, multiply both by the same factor, get back the scaled result. It exists because "generate at 1024x1024, then upscale to 2x or 4x that" is such a common pattern that hardcoding the math into a widget every time is annoying, and wiring live numbers means changing your base resolution once updates every downstream upscale target automatically.

Feed it width and height (both default to 1024, adjustable 256–8192 in steps of 16 - the usual ComfyUI latent-dimension granularity) and a factor (an integer from 1 to 8, defaulting to 2). It multiplies straight through and returns width_resized and height_resized. That's the entire node.

Where it fits. The natural pairing is right after SDXL Resolutions (JPS) or Get Image Size (JPS): generate or load at your base resolution, then run those numbers through this node to get a clean upscale target for a second KSampler pass, an Ultimate SD Upscale node, or a latent upscale step. It saves you from doing 1216 × 2 = 2432 in your head, or worse, mistyping it.

The gap you'll hit, and where to go instead. The factor input is an integer, full stop - 1 through 8, nothing in between. That's not an oversight worth working around, it's the node's actual design, and it's the exact thing that trips people up: someone on r/comfyui went looking for a way to scale a resolution by 1.5x specifically because Resolution Multiply only does whole numbers, and ended up writing their own custom node from scratch to get a float multiplier. If you need a fractional scale factor - 1.5x is common for a modest upscale that doesn't blow past your VRAM - this isn't your node. JPS's own Multiply Int Float node is the one built for exactly that: it takes an integer and a float and gives you both an int and a float result, so you can scale a dimension by 1.5 without a workaround. Reach for Resolution Multiply when a clean 2x or 4x is genuinely what you want, and Multiply Int Float when it isn't.

Installing it. ComfyUI Manager, search "JPS Custom Nodes for ComfyUI," or:

cd ComfyUI/custom_nodes
git clone https://github.com/JPS-GER/ComfyUI_JPS-Nodes.git

Restart, find it under JPS Nodes/Math. Delete any older copy of the pack first if you're upgrading - the author calls this out specifically to avoid class-name conflicts. No models, no dependencies beyond the code itself.

Troubleshooting. The main "issue" people run into isn't a bug, it's the integer-only factor described above - now you know it's by design and which node actually solves the fractional case. Beyond that, watch your VRAM at higher factors: multiplying a 1024x1024 base by 4 gets you to 4096x4096, which is a real pixel count for a single latent upscale pass and can OOM on smaller cards even though the node itself does nothing but arithmetic. If you're chaining a big factor into a latent upscale, consider doing it in two smaller hops (2x then 2x again with a sampling pass in between) rather than one 4x jump.