Bandsaw Blade Length Calculator
A bandsaw blade is a closed loop that wraps two wheels, so its length follows directly from geometry. The blade runs straight down each side (two segments equal to the wheel center distance) and wraps halfway around each wheel (two half-wraps that together equal one full wheel circumference). For wheels of equal diameter the result is exactly twice the center distance plus pi times the wheel diameter. This calculator returns the blade length, the two straight runs, and the wrap length so you can order or confirm the right blade for a 14-inch, 18-inch, or any other two-wheel saw. For best results measure your saw, including the tire the blade tracks on.
Bandsaw blade length formula
Straight runs = 2 * center distance
Wrap length = pi * wheel diameter
Blade length = (2 * center distance) + (pi * wheel diameter)
Blade length (ft) = blade length / 12
This assumes two wheels of equal diameter, the standard configuration on consumer and most industrial bandsaws. The two half-wraps around equal-diameter wheels sum to one full wheel circumference.
Measuring notes
- Measure the wheel diameter across the rubber tire surface, where the blade actually rides, not the bare cast rim.
- Set blade tension and tracking to roughly working position before measuring center distance, since the upper wheel moves as you tension.
- The most reliable check is to measure an existing blade: fold it into a single loop, measure across, and double it.
- Manufacturers sell rounded stock lengths; a calculated value within about an inch usually fits within the saw's tension range.
- Always cross-check against the blade length range stated in your saw's manual.
Bandsaw blade length: frequently asked questions
How do I calculate bandsaw blade length?
For a two-wheel bandsaw with wheels of equal diameter, blade length equals twice the center-to-center distance between the wheels plus pi times the wheel diameter. The two straight runs of the blade equal the two center distances, and the two half-wraps around the wheels together make one full circumference.
Where do I measure the wheel diameter?
Measure the diameter of the wheel including the rubber tire the blade rides on, since the blade tracks on the tire surface, not the bare rim. Most saws are described by a nominal wheel size such as 14 inches; confirm by measuring the actual tire surface for accuracy.
What is the center distance?
Center distance is the straight-line gap between the rotational center of the upper wheel and the center of the lower wheel, measured with the tension and tracking set roughly to working position. Because the upper wheel moves to tension the blade, the center distance varies a little across the adjustment range.
Can I just measure my old blade?
Yes, and it is the most reliable method. Lay the blade flat as a single loop, measure across the loop to get half the length, then double it. Or roll the blade along a tape measure. The calculated length is useful when you have no blade to copy or want to confirm a measurement.
Why does my calculated length differ from the blade I bought?
Manufacturers round blade lengths to stock sizes, and your tension setting shifts the upper wheel, changing the center distance. A calculated value within an inch or so of a stock length normally means that stock blade will fit once tension is adjusted. Always confirm against your saw's stated blade length range.
Official sources
- NIST Digital Library of Mathematical Functions: circle and circumference geometry.
- USDA Forest Products Laboratory: sawing and machining of wood.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.