Pipe Measurements & Sizing
It is important to understanding the correct sizing of pipes and fittings. There are several numbers that are used. The first is nominal pipe size (NPS), which is the measurement that defines the size of the pipe. As an example, a 1/2" pipe would have a nominal pipe size of 1/2". This number is different from the actual outside diameter and inside diameter of the pipe. Please see the charts below to see the proper measurements. As an example, note that a 1/2" pipe (NPS) would fit into any fitting that has a 1/2" sizing. A 1/2" pipe nipple would fit into any 1/2" elbow, tee, cap etc.
| Nominal Size | Outside Diameter (OD) Inches | Outside Diameter (OD) MM | Wall Thickness (Inches) | Wall Thickness (MM) | Weight (lb/ft) | Weight (kg/m) |
| 1/8" | 0,405 | 10.3 | 0.068 | 1.73 | 0.24 | 0.37 |
| 1/4" | 0,540 | 13.7 | 0.088 | 2.24 | 0.42 | 0.84 |
| 1/2" | 0,840 | 21.3 | 0.109 | 2.77 | 0.85 | 1.27 |
| 3/4" | 1.050 | 26.7 | 0.113 | 2.87 | 1.13 | 1.69 |
| 1" | 1.315 | 33.4 | 0.133 | 3.38 | 1.68 | 2.5 |
| 1-1/4" | 1.660 | 42.2 | 0.14 | 3.56 | 2.27 | 3.39 |
| 1-1/2" | 1.900 | 48.3 | 0.145 | 3.68 | 2.72 | 4.05 |
| 2" | 2.375 | 60.3 | 0.154 | 3.91 | 3.65 | 5.44 |
| 2-1/2" | 2.875 | 73 | 0.203 | 5.16 | 5.79 | 8.63 |
| 3" | 3.500 | 88.9 | 0.216 | 5.49 | 7.58 | 11.29 |
| 3-1/2" | 4.000 | 101.6 | 0.226 | 5.74 | 9.11 | 13.57 |
| 4" | 4.500 | 114.3 | 0.237 | 6.02 | 10.79 | 16.07 |
| 5" | 5.563 | 141.3 | 0.258 | 6.55 | 14.62 | 21.77 |
| 6" | 6.625 | 168.3 | 0.28 | 7.11 | 18.97 | 28.26 |