Bucket Test Flow Rate Calculator
Measure flow rate the simple way. Time how many seconds it takes to fill a container of a known size, enter both numbers, and get the flow in gallons per minute, gallons per hour and liters per minute.
How to do a bucket flow rate test
- Use a container of a known size, such as a 5 gallon bucket.
- Open the fixture fully and time how many seconds it takes to fill.
- Enter the container size and the fill time to read the flow rate.
Examples
5 gallon bucket in 30 seconds
5 gallon container, 30 seconds to fill
10 gallons per minute, 600 gallons per hour
Frequently asked questions
How do I measure flow rate with a bucket?
Time how long a known container takes to fill, then divide the container size by the fill time in minutes. A 5 gallon bucket in 30 seconds is 10 gallons per minute.
What size container should I use?
A 5 gallon bucket is common, but any known volume works. A larger container filled over a longer time gives a more accurate reading for fast flows.
Why measure flow rate at all?
It tells you a fixture's real output, a well or pump's delivery, or whether an aerator is restricting flow. Many fixtures are rated near 1.5 to 2.5 gallons per minute.
How do I convert gallons per minute to liters per minute?
Multiply gallons per minute by 3.785412. The tool reports liters per minute alongside gallons for you.
Does container shape affect the result?
No. Only the volume and the fill time matter, so any container of a known gallon capacity gives the same flow rate.
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