Free Pipe Volume Calculator
Calculate how much water a length of pipe holds in gallons and litres.
Volume is pi times the inside radius squared times length, times pipes. It is converted to gallons, litres and cubic units, and the water weighs about 1 kg per litre.
How to use the Pipe Volume Calculator
- Enter your values, choosing the units you are working in.
- Read the result and the supporting numbers shown beneath it.
- Check the result against a second method or a reference table before you rely on it.
About the Pipe Volume Calculator
Calculate how much water a length of pipe holds in gallons and litres.
Quick, reliable engineering arithmetic saves time on site and in the workshop. These tools show their working so you can check the result.
Getting started with the Pipe Volume Calculator
Using the pipe volume calculator takes a minute or two. Your entries are saved in this browser, so you can come back later and carry on.
Tips for better results
Use the inside diameter, not the nominal size, as wall thickness varies. For pressure testing or sizing, consult codes and a licensed plumber.
Keep units consistent from start to finish.
These tools are for estimates. Safety critical designs need a qualified engineer.
Privacy and where your data goes
Everything you type into the pipe volume calculator stays on your own device. Zapxa does not receive your numbers or documents. If you clear your browser data, your saved entries will be removed, so download a PDF of anything you want to keep.
Frequently asked questions
Should I use the inside or outside diameter?
Inside diameter, because only the bore holds fluid. Nominal pipe sizes often differ from the actual bore.
How much does water in a pipe weigh?
About 1 kg per litre, or 8.34 lb per US gallon. The calculator shows this in pounds and kilograms.
Is the pipe volume calculator free?
Yes. It is free to use with no signup, no watermark and no usage limits.
Is my data private?
Yes. Your inputs are processed in your browser and saved only in its local storage. They are not uploaded to our servers.
Does it work on mobile?
Yes. Zapxa works on phones, tablets and desktops. Use the print button or download a PDF to keep a copy.
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