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Engineering

Pipe Flow Calculator

Solve flow rate or velocity with continuity Q = V × A.

Everything is calculated in your browser. Nothing you enter is sent anywhere.

Tool

Solve for

Everything is calculated in your browser.

Pipe dimensions

Why Dockzio?

Simple tools that respect your time and your privacy.

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Open a tool and get to work immediately.

Private by design

Processing happens locally in your browser whenever possible.

Beautifully built

Clean, fast interfaces designed for everyday productivity.

About the pipe flow calculator

Calculate volumetric flow rate or average velocity in a full, circular pipe using the continuity equation Q = V × A.

How it works

Enter the pipe inner diameter and either a target velocity or a known volumetric flow rate. Cross-sectional area A = π/4 × D² links velocity and flow rate. Results include m³/s, L/min, and GPM.

When to use it

Quick sizing sanity checks — verifying that a chosen pipe diameter gives a reasonable velocity for a given flow, or estimating flow from a measured velocity profile average.

Limitations

This tool implements steady, incompressible, fully-developed flow filling the entire cross-section. It does not model pressure drop, friction losses (Hazen-Williams, Darcy-Weisbach), roughness, fittings, or partially filled pipes. Do not use it for head-loss, pump selection, or hydraulic grade line work.

Privacy first

All calculations run locally in your browser. Nothing you type is sent to a Dockzio server.

FAQ

Quick answers to common questions.

Yes. Pipe Flow Calculator is free to use with no account required.