Download Free Nominal Pipe Size Chart from PH Tool
Source: PH Tool
Have you ever been confused by the unconventional system used to delineate pipe dimensions? Why does 10-inch NPS pipe actually measure 10.750 inches, but 14 NPS has an actual outside diameter of 14.000 inches? Is there a difference between schedule 40, STD, and 80S? Rest assured; you are not alone!

The American Standards Association authorized the organization of pipe sizes way back in 1927. Ninety-one years ago there were only three wall thicknesses; STD, XS, and XXS. In 1939, realizing more thickness options were required, the schedule numbers we all recognize today were added. And in 1949 the thinner wall thickness schedules of 5 and 10 were introduced in response to the growing demand for stainless steel pipe. With all of these changes so long ago it is not hard to imagine why many of us scratch our heads when specifying and ordering pipe and pipe-related items.

Download Chart Here

Now for the good part!

PH Tool has created a simplified Nominal Pipe Size Chart for easy reference on your most complex projects. This chart details things such as:

Nominal pipe size

Outside diameter

Schedule designations/wall thickness

Inch and Metric dimensions in easy-to-read color-coded text

1/8 to 48 inch NPS

Visit to download your free copy of this chart.