Sand belt measuring guide

How to Measure a Sanding Belt

Choose the method that matches your belt. Use the same unit for the width and length measurements.

Used belt — cut open

Open the belt at its joint, lay it flat, then measure the full length from one cut end to the other.

A used sanding belt cut open and laid flat, with an L-shaped square at one cut end and a tape measure alongside it.
Measure the full flattened belt from end to end, then measure its width.
  1. Remove the used belt from the machine.
  2. Cut through the belt joint and lay the belt flat without overlapping the ends.
  3. Measure from one cut end to the other for the full length. Measure across the belt for its width.

Belt size = width × full length

New belt — loop laid flat

Lay the uncut loop flat and measure one straight side from bend to bend.

A new sanding belt loop laid flat, with a tape measure running along the centre of one straight section and an L-shaped square at the left.
Measure one straight side of the flat loop. The complete loop length is twice that measurement.
  1. Lay the belt loop flat on a surface without twisting or stretching it.
  2. Measure one straight side from the beginning of the curve to the beginning of the opposite curve.
  3. Double the straight-side measurement to estimate the full belt length. Measure the belt width separately.

Belt size = width × (one straight side × 2)

Calculate the new belt size

Enter the belt width and the one straight-side measurement. The calculator doubles the side measurement to estimate the full belt length.

Enter both measurements to see the new belt size.

Result: width × estimated full length. Keep both measurements in the same unit.