Working out how to get a pile of parts out of a sheet of plywood is one of those jobs that seems like it should be quick, and then isn’t. You sketch a layout, realise two parts overlap, redraw it, forget the saw kerf, and end up buying a second sheet you might not have needed.
This tool does that arrangement for you. Enter the parts you need and the sheet you’re buying, and it returns a cutting layout, a sheet count, an efficiency figure, and — usefully — an ordered list of cuts to make.
(If you searched for a cut list optimizer with a z, you’re in the right place — same tool, American spelling.)
The optimiser packs your parts onto as few sheets as possible while respecting three constraints that most quick sketches miss:
It also reports the offcuts, with dimensions, so you know what’s worth keeping for the next project rather than what’s genuinely scrap.
The tool opens with a small example already loaded — a three-part cut list on a full 2440×1220mm sheet with a 3mm kerf:
| Part | Size | Qty | Grain |
|---|---|---|---|
| Side | 800 × 400 | 2 | Length |
| Shelf | 750 × 350 | 3 | Any |
| Back | 780 × 380 | 1 | Any |
That’s six parts in total, and the result is:
Sheets needed: 1
Efficiency: 57.9% used
Waste: 42.1% (including usable offcuts)
Cuts: 9 (7.9 m of cutting)
Largest offcut: 2440 × 464
The interesting number there is the largest offcut. A 2440×464mm strip is not scrap — it’s most of a shelf for the next job. The waste figure counts it as waste because it isn’t part of this project, which is why the two numbers are reported separately rather than rolled into one.
The cut sequence for that layout begins with a rip at y=400 running the full 2440mm length of the sheet, then crosscuts at x=800 and x=1603 within that strip. Working in that order means each cut is made on a piece that’s still fully supported, which is the practical reason the sequence is given rather than left to you.
If the efficiency looks poor, the usual causes are worth checking in this order: parts locked to a grain direction that don’t need to be; a sheet size that doesn’t suit your part sizes; or one oversized part forcing an awkward split. Changing the sheet preset is often the quickest experiment — a job that wastes half a full sheet sometimes fits neatly on a half sheet or a 2440×610 rip.
It’s worth saying plainly that no optimiser removes the need to think about the material. Grain matching across visible faces, working around a defect, keeping the good face up — those are decisions the layout can’t make for you, and they sometimes justify a less efficient cut.
It's a tool that works out how to arrange your parts on standard sheet material so you use the fewest sheets and waste the least. You enter the parts you need and the sheet size you're buying, and it returns a cutting layout, the number of sheets required, and the offcuts you'll be left with.
Both, depending on where you are. British English uses 'optimiser' and American English uses 'optimizer' — they're the same tool and this page works for either spelling. You'll see the same split with 'mitre' and 'miter' joints, and with 'minimise' and 'minimize'. This site is written in British English because it's built in London, but nothing here depends on which spelling you searched for.
A guillotine cut runs edge to edge across whatever piece you're cutting, all the way through. It matters because that's the only kind of cut a table saw or track saw can actually make — you can't stop halfway across a sheet. Layouts that ignore this look efficient on screen but can't be cut in a real workshop, so every layout here is guillotine-feasible by construction.
The kerf is the width of material the blade turns into dust — typically around 3mm, or an eighth of an inch. Every cut consumes that much, so a layout planned without it will come up short once you've made a dozen cuts. Set the kerf to match your blade and the spacing is accounted for.
Setting a part's grain to Length or Width stops the optimiser rotating it. Sheet material has a visible face grain running along its length, and on visible parts you usually want that running a specific way. Parts set to Any can be rotated freely, which usually improves the packing.
The layout already accounts for kerf, so the sheet count is honest. What it can't know about is damage, mis-cuts, or a defect you find once the sheet is open. Buying one spare sheet on a large job is a reasonable habit, though on a single-sheet job the offcut report usually tells you whether you've got room to recover.