1/4" NPT Thread Specifications
Complete dimensions for 1/4" NPT pipe thread. TPI: 18, Pitch: 0.05556" (1.411 mm).
Thread Dimensions
| Designation | 1/4" NPT |
| Nominal Pipe Size | 1/4" |
| TPI | 18 |
| Pitch | 0.05556" (1.411 mm) |
| Outside Diameter | 0.54" (13.72 mm) |
| Pitch Diameter | 0.5039" (12.8 mm) |
| Minor Diameter | 0.4718" (11.98 mm) |
| Taper Angle | 1.7899° (1:16 taper ratio) |
| Thread Depth | 0.03849" (0.978 mm) |
Tap Drill Size
Tap drill: 0.4718" (11.98 mm)
Common Applications
- Plumbing connections
- Gas piping
- Hydraulic fittings
- Pneumatic connections