8x4 Sheet Cutting Calculator (2440 × 1220 mm)
Enter your cutting list in millimetres and get a layout for 2440 × 1220 mm sheets of MDF, plywood or chipboard. It counts the sheets you need, draws every cut, and takes the 3 mm saw kerf out of each one. It is free, runs in your browser, and needs no signup. The worked example below was laid out by the same optimizer.
Worked example: an alcove cupboard in 18 mm MDF
A typical UK alcove job: a 900 mm wide, 750 mm high, 400 mm deep base cupboard with two doors, plus three 900 × 250 mm shelves for the alcove above. The top, bottom, fixed shelf and plinth sit between the sides, so they are 900 − 2 × 18 = 864 mm long. The doors are full overlay: 447 × 668 mm with a 3 mm centre gap.
| Part | Qty | Size (mm) | How it's sized |
|---|---|---|---|
| Side | 2 | 400 × 750 | full height |
| Top / bottom | 2 | 400 × 864 | 900 − 2 × 18 |
| Fixed shelf | 1 | 380 × 864 | 900 − 2 × 18, set back 20 |
| Plinth | 1 | 80 × 864 | 900 − 2 × 18 |
| Door | 2 | 447 × 668 | (900 − 3 − 3) ÷ 2 × (750 − 80 − 2) |
| Alcove shelf | 3 | 250 × 900 | alcove width |
The parts add up to 2.96 m², and one sheet is 2.98 m². Area maths says one sheet. The real layout needs 2 sheets (50% overall yield), because the parts cannot be squeezed into the gaps around each other once every cut loses 3 mm. The last sheet carries only 2 parts, which leaves a large offcut for the next job.
How many parts fit on one 8x4 sheet?
Each row is a single-sheet run of the optimizer on 2440 × 1220 mm with a 3 mm kerf. Parts can be turned, so these counts assume a plain board with no grain direction.
The 3 mm kerf, and why half a sheet is 608.5 mm
A circular saw, track saw or panel saw blade removes about 3 mm of board on every cut. One rip down the middle of a 1220 mm sheet leaves two strips of 608.5 mm, not 610. Three equal rips leave 404.7 mm each. Plans that ignore the kerf come up 1.5–3 mm short on the last piece of every strip.
The calculator applies the kerf to every cut it draws. If you use a thin-kerf blade, set the kerf to match and the layout updates.
8x4 is not the same size everywhere
- UK and Ireland: MDF and plywood are sold as 2440 × 1220 mm (for example Wickes 18 mm MDF, B&Q 18 mm softwood ply).
- Australia: MDF is commonly 2400 × 1200 mm, with 2700 and 3600 mm lengths too (Precision Plywood). Use the calculator at 2400 × 1200.
- South Africa: MDF is commonly 2750 × 1830 mm (Boardmaster). Use the calculator at 2750 × 1830.
- Sheet metal: UK stockists often sell "8ft × 4ft" as 2500 × 1250 mm (Rackerman), not 2440 × 1220.
The full table, with Europe's 2800 × 2070 chipboard, 2500 × 1250 OSB and Latin American melamine sizes, is in the sheet size atlas.
FAQ
What size is an 8x4 sheet in mm?
In the UK and Ireland, 8x4 sheets of MDF and plywood are sold as 2440 × 1220 mm, slightly bigger than an exact 96" × 48" (2438.4 × 1219.2 mm). In Australia, MDF is commonly sold as 2400 × 1200 mm. UK sheet metal stockists often call 2500 × 1250 mm "8ft × 4ft". Check the actual size on the label before you plan cuts.
How many cuts can I get from a 2440 × 1220 sheet?
It depends on the part sizes and the saw kerf. With a 3 mm kerf, a sheet gives 8 pieces at 600 × 600, 16 at 600 × 300, or 32 at 300 × 300 (see the table above). For a mixed cutting list, enter the parts in the calculator and it lays them out for you.
Why is half a sheet 608.5 mm and not 610 mm?
Because the saw takes its kerf out of the middle. 1220 − 3 = 1217, and half of that is 608.5 mm. Plan two 610 mm wide parts from one width and the second one comes out short.
Will the store cut my sheets to size?
Many UK DIY stores and timber merchants offer in-store cutting, usually on a panel saw, with a limit on cuts or a per-cut charge. Bring a printed cutting list with the rip cuts first. Policies change by store, so check before you go.
Is this calculator free?
Yes. Open the optimizer, enter your parts in millimetres, and it lays them out on 2440 × 1220 sheets in your browser, with no signup.