Sum Integers

Two integers in, their sum out - once as an integer and once as a string. The README says it best: "Simple node that sum two integers, no more no less." If you're wondering why this needs to be a node at all, you're in good company: when the pack launched on r/StableDiffusion, the top comment was literally "I can't believe it still takes custom nodes to do basic math operations."

So let's be honest about when this earns its place and when it's pure filler.

The honest take

Modern ComfyUI lets you type formulas straight into integer widgets - 1024/2 in a width field computes on the fly. For plain arithmetic on hand-entered numbers, you don't need this node. Where it does earn its keep is the moment the numbers aren't typed but wired in. When one of your numbers comes from another node's INT output - a batch count, an index, a seed derived somewhere else - you need a node to combine them, and that's exactly what this is: a two-input adder you can plug into the graph.

The second output is the sleeper. sum_str gives you the sum as a string, which is awkward to produce from the INT output alone. That makes this genuinely useful for text assembly - a dynamic prompt, a filename, a log line where you need the computed total interpolated as text.

Inputs and outputs

Two required inputs, both integers with a minimum of 0:

• int_1 - first number.
• int_2 - second number.

Two outputs:

• sum_int - the sum as an integer, for arithmetic and comparisons.
• sum_str - the same sum as a string, for text and prompts.

One caveat worth knowing: the widget minimum is 0, so you can't type a negative number into either field directly. Values wired in from other nodes can still be negative - the node itself doesn't care - but if you reach for the widget, you're stuck with non-negative inputs. That's a real limitation if you're subtracting by feeding in a negative; the workaround is to compute the negative elsewhere and wire it in.

Install

Manager → search "ComfyUI-northTools", or:

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

then restart. No models, no extra dependencies - requirements.txt is pillow, numpy, torch, all already in ComfyUI.

Is this the node that makes the pack worth installing? No. But it's a zero-cost utility, it does what it says without surprises, and the string output is a legitimately handy addition you won't find in every "add two ints" implementation. Reach for it when your numbers are wired, not typed.