Saw blade kerf: typical widths and how to measure yours

Published October 5, 2026. Kerf figures are published specs from each blade's maker or, where noted, a dealer listing, linked in the table.

Short answer: kerf is the width of the slot a blade cuts, the wood that turns into sawdust. Published specs put full-kerf 10 in. table saw blades at about 0.126 in. (3.2 mm, roughly 1/8 in.), thin-kerf 10 in. blades at 0.091 to 0.098 in. (2.3 to 2.5 mm, roughly 3/32 in.), thin 7-1/4 in. circular saw blades at 0.059 in. (1.5 mm), track saw blades at 2.2 to 2.4 mm and band saw blades at 0.048 to 0.060 in. On a CNC router the kerf is the diameter of the bit. Your own saw may cut a little wider, so measure if accuracy matters.

Kerf by saw and blade

Freud, Diablo and Makita publish kerf in inches; Festool publishes cutting width in millimetres (2.2 and 2.4 mm) and blade thickness (1.6 and 1.8 mm). Converted values are rounded. For the band saw rows, "plate" is the thickness of the blade body. The Timber Wolf steel blade figures are from a retailer listing (Woodcraft); the carbide-tipped blade's are from its maker, Suffolk Machinery.

Why kerf is wider than the blade

A blade's teeth are wider than its body so the body doesn't rub in the cut. Carbide-tipped circular blades get that clearance from tips wider than the plate: Freud's LM72R010 has a 0.087 in. plate and cuts a 0.126 in. kerf. Band saw blades get it from set, the teeth bent alternately left and right: a 0.025 in. Timber Wolf blade cuts 0.048 in. Always use the kerf figure, not the plate thickness.

Full kerf vs. thin kerf

Full-kerf 10 in. blades cluster around 1/8 in. (0.125 in.) and thin-kerf blades around 3/32 in. (0.094 in.). Thin-kerf blades remove less wood, so the saw has less work to do per cut; full-kerf blades have thicker, stiffer plates. For cut list planning the only question is what your blade actually removes.

How to measure your own kerf

Real kerf can differ from the spec: a blade that wobbles (runout), a dull or resharpened blade, or stock that drifts during the cut all change it. Three ways to measure it, from quickest to most precise:

1. Measure a test slot. Cut a few inches into the end of a scrap and stop. On a table saw, switch off and let the blade stop completely before you pull the scrap back. Measure the slot with calipers in a couple of places, or find the drill bit or feeler gauge that just fits.
2. Measure before and after a crosscut. Measure a piece with two square ends, cut it in two and measure both halves. The kerf is the original length minus the two halves. Small measuring errors matter at this scale, so make several cuts and average: if a 24 in. piece becomes five pieces (four cuts) that total 23 1/2 in., the kerf is 1/2 ÷ 4 = 1/8 in.
3. Rip several strips. Measure the width of a board, rip it into strips, and add up the widths of all the pieces, including the last one. The difference divided by the number of rips is your rip kerf, which is the number that matters for sheet goods.

Measure with the blade you'll actually use, and measure again after a blade change or sharpening. If your measurement falls between two fractions, round up: a planned kerf that is slightly too wide costs a sliver of offcut, but one that is too narrow can leave the last part short.

How kerf changes a cut list

Every cut that separates two parts removes one kerf of material. A row of n parts needs n − 1 kerfs between them, plus one more if an offcut is left beyond the last part. Kerf is easy to forget because each cut is thin, but it adds up:

• Strips from a sheet. Four 12 in. strips from a 48 in. sheet need 48 3/8 in. with a 1/8 in. kerf. You get three full strips and one 11 5/8 in. strip.
• Pieces from a board. Four 24 in. pieces from a 96 in. board: three are full length, the fourth is 23 5/8 in.
• Many narrow rips. Ripping 1 1/2 in. strips across a 48 in. wide sheet gives 29 strips with a 0.126 in. blade (29 × 1 1/2 + 28 × 0.126 = 47.03 in.) but 30 with a 0.091 in. blade (30 × 1 1/2 + 29 × 0.091 = 47.64 in.).
• Sixteen cuts. At 0.126 in. per cut, 16 cuts turn 2.02 in. of material into dust; at 0.091 in. it is 1.46 in.

The cut list optimizer and the board cut calculator place exactly one kerf between neighboring parts and between a part and an offcut, but none at the trimmed edge of a sheet or the end of a board. So if you set an edge or end trim, enter the full width each cleanup cut removes, blade kerf included: skimming an edge with a 1/8 in. blade takes at least 1/8 in. If a cut will be rough and need cleaning up, for example a freehand circular saw cut, enter a kerf a little larger than the blade's so each part gets room for the cleanup pass.

Which side of the line?

The kerf has to come out of something. Mark each part's size, then cut with the blade on the waste side of the mark so the line stays on the part. When you cut several parts in a row from one strip, measure each one from the freshly cut end, not from your original marks, so one kerf per cut is all you lose.

Related

• Plywood sheet sizes and actual thickness
• How many sheets of plywood do I need?
• How the optimizer handles kerf, trim and grain