On an underpowered saw, yes — it removes less material, so the motor works less. On a powerful saw it mainly wastes less timber, and it deflects more, which shows as a slightly less flat cut face.
Kerf is the width of material the blade removes. A standard blade takes around 3 mm (0.12 in); a thin kerf blade takes closer to 2 mm (0.08 in).
Where it genuinely helps
Less material removed means less work for the motor. On a saw at the lower end of the power range, a thin kerf blade is the difference between a rip in 50 mm oak that bogs down and one that does not. That is the reason to buy one.
It also wastes less timber. Over a stack of expensive hardwood ripped into narrow components the saving is real, though it rarely pays for the blade on its own.
The cost
A thinner steel body is less stiff. It deflects more under side load, which shows as a cut face that is slightly less flat and a blade that is more sensitive to a fence out of parallel or a hurried feed. It also runs hotter, because there is less steel to carry heat away.
What it means for the riving knife
The knife must be thinner than the kerf and no thinner than the blade body. A standard riving knife behind a thin kerf blade will not pass, and that is not a thing to work around — it means fitting the thinner knife the manufacturer supplies.
Last reviewed 2026-08-12