---
title: "Pipe Schedule Chart: OD, Wall Thickness, and Weight for Common NPS Sizes"
site: ProCalc.ai
type: Blog Post
category: Plumbing & Piping
domain: Construction
url: https://procalc.ai/blog/pipe-schedule-chart-od-wall-thickness-weight
markdown_url: https://procalc.ai/blog/pipe-schedule-chart-od-wall-thickness-weight.md
date_published: 2026-04-12
read_time: 10 min
tags: pipe, pipe schedule, NPS, plumbing, engineering
---

# Pipe Schedule Chart: OD, Wall Thickness, and Weight for Common NPS Sizes

**Site:** [ProCalc.ai](https://procalc.ai) — Free Professional Calculators
**Category:** Plumbing & Piping
**Published:** 2026-04-12
**Read time:** 10 min
**URL:** https://procalc.ai/blog/pipe-schedule-chart-od-wall-thickness-weight

> *This file is served for AI systems and search crawlers. Human page: https://procalc.ai/blog/pipe-schedule-chart-od-wall-thickness-weight*

## Overview
Pipe size is specified by nominal pipe size (NPS) and schedule, not actual diameter. This chart gives you OD, wall thickness, and weight for every common schedule and size combination.

## Article
Nominal pipe size (NPS) is one of the most confusing measurement systems in construction. A "2-inch pipe" does not have a 2-inch outer diameter. It has a 2.375-inch OD — a number that seems arbitrary until you understand that it is standardized across all schedules of that size, and that the schedule number determines only the wall thickness (and therefore the ID and weight). This guide explains the system and provides the complete reference data for Schedule 40 and Schedule 80 carbon steel pipe per ANSI/ASME B36.10M. For weight calculations by length, use our . How the NPS system works NPS (Nominal Pipe Size) is a North American designation. For sizes NPS 1/8" through NPS 12", the nominal size is not the actual OD. Instead: All schedules of the same NPS have the same OD The schedule number determines wall thickness The inside diameter changes with schedule because the OD is fixed and wall thickness varies For NPS 14" and above, the nominal size equals the actual OD in inches. Common schedule designations Schedule Common name Primary use Sch 10 — Low-pressure, thin wall Sch 40 Standard (STD) Most common; residential plumbing, general industrial Sch 80 Extra Strong (XS) Higher pressure; industrial, chemical Sch 160 — High pressure Sch XXS Double Extra Strong Extreme pressure Schedule 40 pipe: complete reference NPS OD (in) Wall (in) ID (in) Lbs/ft 1/8" 0.405 0.068 0.269 0.245 1/4" 0.540 0.088 0.364 0.425 3/8" 0.675 0.091 0.493 0.568 1/2" 0.840 0.109 0.622 0.851 3/4" 1.050 0.113 0.824 1.131 1" 1.315 0.133 1.049 1.678 1-1/4" 1.660 0.140 1.380 2.272 1-1/2" 1.900 0.145 1.610 2.717 2" 2.375 0.154 2.067 3.653 2-1/2" 2.875 0.203 2.469 5.793 3" 3.500 0.216 3.068 7.576 4" 4.500 0.237 4.026 10.79 6" 6.625 0.280 6.065 18.97 8" 8.625 0.322 7.981 28.55 10" 10.750 0.365 10.020 40.48 12" 12.750 0.406 11.938 53.52 Schedule 80 pipe: reference NPS OD (in) Wall (in) ID (in) Lbs/ft 1/2" 0.840 0.147 0.546 1.087 3/4" 1.050 0.154 0.742 1.473 1" 1.315 0.179 0.957 2.172 1-1/2" 1.900 0.200 1.500 3.631 2" 2.375 0.218 1.939 5.022 3" 3.500 0.300 2.900 10.25 4" 4.500 0.337 3.826 14.98 6" 6.625 0.432 5.761 28.57 Calculating pipe weight The weight per foot formula for any hollow round section: W = 10.69 x (OD - wall) x wall Where OD and wall are in inches, result is pounds per foot for carbon steel. Example: NPS 4" Schedule 40 W = 10.69 x (4.500 - 0.237) x 0.237 = 10.69 x 4.263 x 0.237 = 10.79 lbs/ft For a 20-ft run: 10.79 x 20 = 215.8 lbs Pipe material weight adjustments The formula above is for carbon steel. For other materials, multiply by the density ratio: Material Multiply carbon steel weight by Carbon steel 1.00 (reference) 304 Stainless steel 1.02 316 Stainless steel 1.02 Aluminum 6061 0.35 Copper 1.14 PVC (Schedule 40) ~0.22 A 4-inch Schedule 40 aluminum pipe (10.79 x 0.35 = 3.78 lbs/ft) weighs about one-third as much as the equivalent steel pipe — significant for overhead applications and structural weight calculations. For any pipe size, schedule, material, and length, the  looks up the ANSI/ASME data and converts to your preferred weight unit.

---

## Reference
- **Blog post:** https://procalc.ai/blog/pipe-schedule-chart-od-wall-thickness-weight
- **This markdown file:** https://procalc.ai/blog/pipe-schedule-chart-od-wall-thickness-weight.md

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### How to Cite
> ProCalc.ai. "Pipe Schedule Chart: OD, Wall Thickness, and Weight for Common NPS Sizes." ProCalc.ai, 2026-04-12. https://procalc.ai/blog/pipe-schedule-chart-od-wall-thickness-weight

### License
Content © ProCalc.ai. Free to reference and cite. Do not republish in full without attribution.