Lumber cut calculator
Enter your board lengths, saw kerf, and cut list, then mark knots or checks as blocked zones. The calculator lays out each board and shows the leftover after cutting.
Reading the bars: parts are outlined boxes · kerf is a solid black band · blocked zones are grey · drop has a dashed border · scrap is hatched.
Use it for Lumber
Get the most out of every board. Enter your stock — 8, 10, 12, or 16 ft dimensional lumber or rough boards — and your cut list, mark the knots and checks you need to cut around, and let the optimizer lay out the rest.
Lumber cut calculator questions
Can it cut around knots and defects?+
Yes — that's what blocked zones are for. Mark each knot, check, or waney span on a board and the optimizer places your cuts around them. Most cut calculators can't do this at all.
What kerf should I enter for my saw?+
Most circular and miter saw blades cut a 1/8 in kerf; thin-kerf blades take 3/32 in. Table saws are similar — check your blade or measure a cut.
Does it work in board feet?+
No — it optimizes lengths, not volume or sheet goods. For plywood and panels you want a 2D panel optimizer; for everything cut to length from a board, you're in the right place.
Can I label my cuts?+
Yes. Name each cut — stile, rail, leg, shelf — and the labels follow through to the layouts, the printed plan, and the CSV.
Can I mix board lengths in one run?+
Yes. Add a stock row per length you have, each with its own quantity and minimum drop, and the optimizer picks the best board for every cut.