About the Faucet Flow Rate Calculator
Measure a tap or shower flow rate by timing how long it takes to fill a container.
Also known as: tap flow rate, shower flow rate test, gpm test, bucket test flow.
How to use this calculator
- Enter container volume, time to fill, usage per day, water cost per m³.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
L/min = container litres ÷ seconds × 60
Worked example
Using the values pre-filled in the calculator above:
- Container volume = 10 litres
- Time to fill = 45 s
- Usage per day = 20 min
- Water cost per m³ = 1.8
the calculator returns:
- Flow rate: 13.33 L/min
- In US gallons per minute: 3.522
- Litres per second: 0.2222
- Daily usage: 266.7 litres