Flow rate calculator

Volumetric flow rate = volume ÷ elapsed time.

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Volume

Elapsed time

Answer

…

Volumetric flow rate = volume ÷ elapsed time.

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Precision and calculation record

Decimal places in numeric results and text downloads

Rounding changes displayed numbers, not the calculation. Text, fractions, matrices and CSV schedules keep their own formatting. Automatic keeps up to 12 significant digits, with money shown to cents where applicable.

Step-by-step calculation

Inputs are substituted below. Each line evaluates the next operation; intermediate values are displayed to 12 significant digits while the calculation uses full precision.

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Formula and assumptions

The result uses your volume unit per time unit. It is an interval average, not a prediction of pressure or pipe performance.

Automatic precision shows numbers to 12 significant digits. Thousands separators such as 1,000 are accepted; use a dot for decimals.

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Updated 2026-09-26

Using Flow rate calculator

Volumetric flow rate = volume ÷ elapsed time.

The result uses your volume unit per time unit. It is an interval average, not a prediction of pressure or pipe performance.

Next: Mass calculator

A worked example

With volume = 120, elapsed time = 4, the volumetric flow rate is 30.

Next: Pressure calculator

Before you use the result

The result uses your volume unit per time unit. It is an interval average, not a prediction of pressure or pipe performance.

Example results for volume

These examples use Elapsed time: 4. They are reference calculations, not recommended settings.

Volume	Volumetric flow rate
60	15
120	30
240	60

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