Pipe Schedule Chart — NPS 1/8 to 24 (DN 6–600)
Welded and seamless steel pipe per ASME B36.10M / EN 10220
Every standard pipe size from NPS 1/8 (DN 6) to NPS 24 (DN 600). The outside diameter is fixed per size; the schedule number sets the wall. Click a size for its full page with every schedule — wall, inside diameter, kg/m and lb/ft.
Pipe sizes — NPS 1/8 to 24
Frequently Asked Questions
What does pipe schedule mean?
Schedule is a wall-thickness series: the higher the number, the thicker the wall at the same outside diameter. OD never changes within a size, so fittings, flanges, and threads stay interchangeable — only pressure capacity and the bore change.
What is the difference between NPS and DN?
NPS is the North American inch-based name, DN the European millimeter-based one — NPS 2 = DN 50 is the same pipe. Both are nominal labels: the real OD of NPS 2 is 60.3 mm, not 50.8. The pages here list both names for every size.
How is pipe weight calculated?
kg/m = (OD − t) × t × 0.02466, with OD and wall t in millimeters — the standard plain-end mass formula from EN 10220 / ASME B36.10M at 7,850 kg/m³. Example: 2" Sch 40 → (60.3 − 3.91) × 3.91 × 0.02466 = 5.44 kg/m.
STD, XS and XXS — what are they?
The older weight-class names: Standard, Extra Strong, Double Extra Strong. STD equals Sch 40 up to NPS 10 and stays at 9.53 mm above; XS equals Sch 80 up to NPS 8 and stays at 12.7 mm above; XXS has no schedule equivalent for most sizes.
Values are entered from the governing standard’s published tables and cross-checked programmatically against its mass and section formulas before publication. Spotted an error? Write to advertising@metalabout.net — verified corrections ship within days. About