How much water does a pipe hold?
Enter the inside diameter and length — get the volume instantly.
Pipe dimensions
Volume held
19.63 L
A 50 mm pipe, 10 m long, holds about 19.63 L of water when full.
Uses inside diameter. For capacity/flushing/chlorination estimates.
Common questions
- How do you calculate the volume of water in a pipe?
- Volume = π × (inside radius)² × length. Enter the pipe's inside diameter and its length and the calculator returns the volume, in litres or gallons.
- Should I use inside or outside diameter?
- Inside diameter — that's the actual space water occupies. Nominal pipe sizes differ from the true inside bore, so use the real inside diameter for accuracy.
- What is pipe volume used for?
- Chlorination and disinfection dosing, flushing and purging a line, antifreeze for winterizing, and estimating how much water a run holds.
Reference & education only. Not professional, engineering, or code-compliance advice. Estimates are based on published model codes; local amendments and your Authority Having Jurisdiction (AHJ) govern. Always verify against the current adopted code and a licensed professional before doing work.
Last reviewed 2026-06.