Cut list calculator: fewer boards to buy

A cut list says which pieces to cut and how many boards to buy. The saw kerf, the width of the blade's cut, is what most hand calculations forget.

How do you make a cut list?

List every piece with its length and quantity, add the kerf for each cut, and fit the pieces on stock lengths, longest first. A cut list optimizer does the same search for the arrangement that leaves the least waste.

Why does the kerf matter?

A typical saw blade removes about 1/8 in. Three cuts cost 3/8 in, which can decide whether the last piece fits on the board.

Example. Three pieces of 30 in from one 8 ft (96 in) board: 3 × 30 = 90 in, plus 3 cuts × 1/8 in = 90 3/8 in. They fit, with 5 5/8 in left over.

Actual lumber sizes

A "2x4" is 1 1/2 in by 3 1/2 in. Plan around the real size, not the name, when pieces are joined side by side.

Cutting sheets of plywood

Sheet goods are fitted in two dimensions: rows of pieces across a 4 ft by 8 ft sheet, with a kerf between them. The lower bound is the total piece area divided by the sheet area, rounded up.

Cut lists in Clad

Clad's cut list finds the boards to buy on as few stock lengths as it can, with the kerf included, and draws the boards. A second view, "at the saw", shows each cut measured from both ends so you can tick it off. A separate sheet cut list does plywood and similar.

See what Clad does. Clad is coming soon to the iPhone.

More guides

How this page was made

Written with the help of an AI assistant (Claude, by Anthropic). Every worked example was computed again by a program and checked against its formula. Building codes differ by place: check yours before you build.