Pipe Flow Sizing
Whether your pipe handles your fixtures simultaneously.
Fixtures running simultaneously
Capacity OK
0.0 / 14 gpm
14.0 gpm headroom · ~50 psi at delivery
Sizing is rough. PEX has higher flow at the same nominal size because it's measured by inside diameter while copper is outside diameter. For a code-compliant install, follow your local plumbing code (UPC or IPC) and use a fixture unit calculation.
About
Pick material, diameter, supply pressure, and run length. Tick fixtures running at once. The tool checks if total demand fits the pipe's GPM capacity and estimates pressure at the fixture.
How to use
- Pick material and diameter.
- Tick fixtures.
FAQ
PEX or copper?+
PEX is cheaper, easier to install, and resists freezing better. Copper lasts longer and is preferred for hot water lines in some codes. Both are common in modern construction.