1/2 inch pipe calculator
half inch pipe calculator
1/2 pipe flow rate

1/2 Inch Pipe Calculator & Complete Guide

Calculate flow rates, capacity, and sizing for 1/2 inch pipes. Complete guide to 1/2" pipe specifications, applications, and flow capacity for copper, PEX, PVC, and CPVC.

PlumberCalc Team
Updated 1/24/2026

1/2 inch pipe is one of the most common sizes used in residential plumbing systems, typically serving as branch lines to individual fixtures. Understanding the flow capacity, applications, and proper sizing for 1/2" pipe is essential for plumbers and contractors. This comprehensive guide covers everything you need to know about 1/2 inch pipe, including flow rates for different materials, common applications, and code requirements.

Key Characteristics

Nominal Size

1/2"

Inside Diameter

0.485" - 0.622" (varies by material)

1/2" Pipe Flow Capacity by Material

Maximum recommended flow rates (GPM) for 1/2" pipe at standard velocity (6 ft/s). Actual capacity varies with pressure, temperature, and pipe length.

MaterialInside DiameterC-ValueMax Flow @ 6 ft/s (GPM)Typical Use
Copper (Type L)0.545"1404.2Water supply, standard
PEX0.485"1503.3Flexible installation
CPVC0.485"1503.3Hot/cold water
PVC0.485"1503.3Cold water only

Frequently Asked Questions

Code Compliance

1/2" pipe is approved for branch lines to fixtures per IPC and UPC codes. Minimum size for fixture supply lines is typically 1/2". Always verify local code requirements as some jurisdictions may have specific restrictions.