Band Saw Blade Width and TPI Calculator

How it works

A band saw blade can follow a curve only down to a minimum radius that depends on its width: the narrower the blade, the tighter the curve. The page reads the minimum radius chart on the Olson Saw Resources page (modified 2026-03-17) and reports the widest blade whose minimum radius is no larger than the tightest curve in the pattern. Every narrower blade in the chart has a smaller minimum radius, so it can cut the curve too.

Tooth pitch is set by how many teeth are in the wood at once, which is the teeth per inch (TPI) times the stock thickness in inches. Olson Saw's rule is to keep at least 3, preferably 6, teeth in the material. Dividing the fewest and most teeth you want in the cut by the thickness gives the TPI range; thicker stock calls for coarser blades.

Olson's own TPI table lists 2–3 TPI for resawing stock 4 in to more than 8 in thick, 4 TPI for 2–6 in, 6 TPI for general cutting of 1–4 in stock, 10 TPI for 1/2–2 in and 14 TPI for 1/4–1 in.

Formula

widest blade  = largest width w with minimum radius(w) ≤ R
TPI (coarsest) = fewest teeth in cut ÷ thickness(in)
TPI (finest)   = most teeth in cut ÷ thickness(in)
chart (in): 1/8 → 3/16, 3/16 → 5/16, 1/4 → 5/8, 3/8 → 1-1/2, 1/2 → 2-1/2, 5/8 → 4, 3/4 → 5-1/2, 1 → 7

Example

A pattern whose tightest curve has a 3 in radius, cut in 3/4 in stock: the 1/2 in blade (minimum radius 2-1/2 in) is the widest that can follow it; the 5/8 in blade needs 4 in.

Keeping 3 to 12 teeth in 3/4 in stock takes 3 ÷ 0.75 = 4 to 12 ÷ 0.75 = 16 TPI, and Olson's preferred 6 teeth is 8 TPI.

Assumptions and limitations

• The radius chart is one blade maker's published chart (Olson Saw); blade set, tooth style, saw setup and feed rate change the radius a given blade can actually cut.
• The minimum number of teeth (3) is Olson Saw's rule; the maximum is an editable typical figure, not from the maker's chart.
• TPI results are the exact quotients; blades are sold in a limited set of pitches, including variable pitches such as 2/3 or 10/14.
• Metric thicknesses are converted to inches because TPI is a per-inch measure.

Frequently asked questions