What packing method does this use?

It uses a first-fit-decreasing-height shelf heuristic, a well-known approximation for guillotine cutting. Parts are sorted tallest first and dropped onto horizontal shelves across each sheet, opening new shelves and new sheets only when needed.

Is the result the absolute minimum number of sheets?

Not always. Optimal 2D bin packing is computationally hard, so this gives a fast, realistic, near-optimal layout. An experienced cut planner working by hand may occasionally fit parts onto fewer sheets for tricky part mixes.

How does saw kerf affect the count?

Every cut removes a strip of material equal to the blade width. The tool inflates each part by the kerf on both dimensions so the layout reserves room for the saw, which prevents parts coming out undersized.

Can parts be rotated?

Yes. The packer tries each part in both orientations and marks any rotated part with a turn symbol on the diagram. This usually improves utilization, though for grain-matched faces you may want to disable rotation by entering parts at a fixed orientation.

What if a part is bigger than the sheet?

Any part that will not fit on the chosen sheet even when rotated is reported separately as unplaceable. Choose a larger sheet, split the part into joinable pieces, or order oversized stock for those parts.

Plywood Sheet Optimizer

Sheet goods are expensive, and a careless cut order wastes both material and money. This optimizer takes your list of rectangular parts and packs them onto the fewest sheets it can, showing a cut diagram for each one so you can take it straight to the saw.

How it works

The tool uses a first-fit-decreasing-height shelf algorithm, a standard heuristic for guillotine cutting:

1. expand every part by its quantity into individual rectangles
2. add the saw kerf to each rectangle's width and height
3. sort rectangles tallest first
4. place each on the first shelf where it fits, rotating if that helps
5. open a new shelf, then a new sheet, only when nothing else fits

Material utilization is the total area of your parts divided by the total area of the sheets used, so you can see how much offcut a given layout leaves behind.

Example and tips

Cutting four 24×30 panels, six 12×48 strips, and two 36×18 pieces with a 1/8 in kerf typically fits on two 4×8 sheets at roughly 70 to 80 percent utilization. To reduce waste, batch similar heights together, cut long strips first, and keep offcuts labeled for the next job. If grain direction matters, enter parts so the long dimension always runs the same way and treat rotated placements with care.