1.Place your pipe on a flat surface.

2.Measure the outside diameter of the pipe using a micrometer or caliper. Write down that measurement.

3.Measure one inch from the end of the pipe with a tape measure or caliper and make a small mark with a permanent marker.

4.Count the number of threads in that inch. Write down that number. Compare that measurement with a pipe measurement chart.

5.Place your pipe on a flat surface.

6.Measure the outside diameter of that pipe with a micrometer or caliper and write down that measurement.

7.Measure the distance between any two adjacent threads on the pipe in millimeters. Write down that number. This is called the pitch. Compare that measurement with a pipe measurement chart.