Free 18mm plywood cutting plan

What this tool does

It takes the list of parts you need (their length, width, thickness and quantity) and works out how to lay the 18mm parts onto full 18mm plywood sheets with as little waste as possible. Because cutlistlab groups parts by thickness, your 18mm panels stay separate from any 12mm or 6mm parts in the same project, so each sheet holds only parts of the right thickness. Instead of guessing, you get a numbered cutting plan, a clear cut list, and the exact number of 18mm sheets to buy. Everything runs in your browser, with nothing to install and no account needed.

How to use it

1. Enter your parts. Add each part with its length, width, quantity and a thickness of 18mm. Name the parts so they are easy to match against the plan later.
2. Pick your 18mm sheets. Choose a standard sheet (for example 4x8 ft, 1220x2440 mm) in 18mm, or enter your own size. Add 18mm offcuts you already have so they get used first.
3. Set the kerf. Enter the width your saw blade removes per cut so every part comes out exactly to size.
4. Read the plan. The tool packs the 18mm parts onto the fewest sheets, shows the layout as a drawing, lists the cuts in order, and tells you how many sheets you need and how much is left over.

Why 18mm for carcasses and shelves

18mm is the go-to thickness for cabinet carcasses and shelving, which is why it shows up in almost every plywood project. In inches it sits at roughly 23/32 in to 3/4 in nominal, so a North American 3/4 in sheet and a European 18mm sheet do the same job. The thickness gives a carcass enough rigidity for sides, tops and bottoms, holds screws and dowels in the edge without splitting, and keeps a shelf from sagging over a normal span. Thinner panels are fine for backs and drawer bottoms, but for the structural parts most people stay at 18mm, so it pays to plan those cuts well.

A few things make a real difference when you plan 18mm sheets:

• Grain direction. Plywood has a visible grain. Mark a part as grain-fixed and it stays oriented the right way, so the face veneer runs as you want; parts without grain rotate freely to pack tighter.
• Offcuts as stock. Add the leftover 18mm panels from earlier projects and the tool uses them before cutting into a fresh sheet.
• Kerf and trim. The blade width and any edge you trim off a rough sheet are included, so the plan is realistic, not just theoretical.

A worked example

It helps to see how a cut list lands on a sheet of 18 mm plywood. As an example, say you are building a small base cabinet in 18 mm stock and need the parts below. Enter them in millimetres (or inches, both work), set the 18 mm thickness, then pick a goal: least waste, fewest cuts, or lowest cost.

Because the parts share one 18 mm thickness, the calculator keeps the kerf consistent and a list like this typically uses about 1 sheet, with roughly 15% offcut. You get a numbered cutting order for the workshop or the store's panel saw, parts you can rotate or nudge by hand, optional edge-band and label notes, and a CSV export. Any usable offcut goes to your scrap library for the next 18 mm project. Treat the result as an example, not a guarantee: your exact parts and kerf will shift the numbers.

Frequently asked questions