G1/2 vs 1/2-14 NPT: specs compared
Updated 05 September 2026.
21.34 mm
1/2-14 NPT wins on major diameter
On major diameter, 1/2-14 NPT leads: 21.34 mm versus 20.955 mm.
| Spec | G1/2 | 1/2-14 NPT |
|---|---|---|
| Designation | G1/2 | 1/2-14 NPT |
| Major diameter | 20.955 mm | 21.34 mm |
| Threads per inch / pitch | 14 | 14 |
| Thread form | parallel, 55 degree | tapered, 60 degree |
| Seals on | flat washer | on the thread flanks with PTFE tape |
Questions and answers
Which has the higher major diameter, G1/2 or 1/2-14 NPT?
On major diameter, 1/2-14 NPT leads: 21.34 mm versus 20.955 mm.
How do G1/2 and 1/2-14 NPT compare?
On major diameter, 1/2-14 NPT leads: 21.34 mm versus 20.955 mm.