Pipe Sizing Calculator
Static · formula-only · worked example computed when this page was built · no live data
The Pipe Sizing Calculator picks the smallest standard pipe that keeps velocity in the safe economical range for a given flow. Example: for 300 L/min of water through 50 m of PVC pipe, Recommended nominal size = 50 mm, Velocity = 2.31 m/s, Flow = 18 m³/h (per ASHRAE 2021 Ch.22 | PSME Code | PNS ISO 4427).
How it works
Computed from your inputs per ASHRAE 2021 Ch.22 | PSME Code | PNS ISO 4427. Anything the worked example does not state uses this calculator's standard default; the interactive version shows every input and lets you change it.
Worked example (Plumbing & Pumps)
Inputs: 300 L/min of water through 50 m of PVC pipe.
| Result | Value |
|---|---|
| Recommended nominal size | 50 mm |
| Velocity | 2.31 m/s |
| Flow | 18 m³/h |
Computed by WorkHive's calculation engine when this page was built; standard: ASHRAE 2021 Ch.22 | PSME Code | PNS ISO 4427.
How to use this calculator
- Read the worked example. It uses 300 L/min of water through 50 m of PVC pipe and shows every number in the method.
- Follow the formula with your own figures: it returns Recommended nominal size, Velocity, Flow, computed per ASHRAE 2021 Fundamentals Ch.22 | PSME Code | PNS/ISO 4427.
- To compute interactively, open the Pipe Sizing Calculator inside WorkHive's free Engineering Design suite (link below). It runs the same method with your inputs.
FAQ
What is a water pipe size calculator by flow rate?
The Pipe Sizing Calculator is a free online tool that picks the smallest standard pipe that keeps velocity in the safe economical range for a given flow. It shows the formula and a fully worked example so you can check the method, not just the number.
How is it calculated?
The result is computed from your inputs following ASHRAE 2021 Fundamentals Ch.22 | PSME Code | PNS/ISO 4427. The worked example on this page shows a real computation with real numbers.
Is the calculator free?
Yes. WorkHive is free: this worked example is open to everyone, and the interactive calculator runs inside the free Engineering Design suite after a free sign-up (your work is saved to your account). WorkHive is a free, offline-first maintenance platform built for Philippine industrial plants.
Run it on your own numbers
Open the interactive Pipe Sizing Calculator in WorkHive. Free, and a free sign-up saves your calculations, BOMs and scope-of-works to your account.