Saw kerf waste tracker
Kerf is the material your saw blade turns into dust. Most calculators ignore it. On a project with a hundred cuts it can quietly cost you a board foot or two. This one totals up the waste by blade type and shows you what that waste actually cost.
Calculator
Why kerf is more than just dust
Kerf comes off as sawdust, but it was once a board-foot of wood you paid for. On a small project the dollar amount is trivial; on a long production run it adds up. More importantly, kerf is also the mechanical limit on how tight you can cut — you cannot make a cut narrower than your blade.
This is why dovetails are hand-cut, why a thin-kerf blade is genuinely useful for fine work, and why a bandsaw with a 1/4″ blade can cut tighter curves than a bandsaw with a 3/4″ blade. The narrow blade is, mechanically, less rigid — but for a hobbyist cutting curves in 3/4″ stock, that's a worthwhile trade.
Thin-kerf: when it's worth it
Thin-kerf blades (typically 3/32″ instead of 1/8″) save ~25% of kerf volume per cut. They also flex more under load, so they're best on a smaller table saw (under 2 HP) cutting wood under 3/4″ thick. On a 3 HP cabinet saw pushing 8/4 hardwood, a thin-kerf blade will deflect and give you wavy cuts.
Bandsaw kerf depends on blade width, set and tooth shape — anything from 0.025″ (scroll saw) to 0.045″ (general purpose 3/4″ blade). For tight curves, narrower is better at the cost of straight-line stability.
Limitations
- Assumes straight cuts. Curves through thick stock cut more length than the chord of the curve.
- Doesn't count blade thickness variation due to sharpening, or wobble from a worn arbor.
- Doesn't account for blade drift on a bandsaw, which can waste an extra 1/16″ on the side of the cut.
- The board-foot cost calculation uses thickness × length × kerf; for thin stock the number is dominated by length.
Frequently asked questions
Is kerf waste really worth tracking?
For a hobbyist building one project a month, no — it's a rounding error. For a small shop billing clients, yes — the cost adds up, and the calculator helps you choose a thin-kerf blade when the project allows it.
What about laser kerf?
For plywood laser cutting, kerf is more like 0.005–0.015″ depending on material. The geometry changes too (the kerf is conical), so this calculator isn't right for that workflow. Use a laser-specific kerf tester if you need precision fit.
My blade drifts. Does that matter?
Yes — blade drift on a bandsaw typically adds 1/16″ to 1/8″ of waste on the side that catches the force. Fix the drift (re-tension, align the fence, fresh blade) before chasing the kerf number down further.