Woodworking calculators

Woodworking splits its materials into two kinds that are bought in completely different ways, and the calculators here follow that split. Sheet goods — plywood, MDF, melamine — are sold as whole sheets, so the only question that matters is how many sheets your parts fit into and in what arrangement. Solid timber is sold by volume, so the question is how many board feet you are being charged for.

Neither answer comes from a simple multiplication. Sheet goods have to be cut edge to edge with a saw blade that destroys three millimetres of material every pass, so the arrangement of parts changes the sheet count. Timber is priced on nominal dimensions rather than the size that turns up, which is why a planed board still costs what the rough board cost.

Both tools give you the purchase figure first — sheets to buy, board feet to pay for — and the working underneath it. Neither invents a waste allowance for you: sheet waste falls out of the layout itself, and timber waste depends on the grade and the defects in your particular boards, which is a judgement no calculator should make on your behalf.