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Water Flow Unit Conversion Calculator

Convert a steady volumetric flow between liters per minute, liters per second, cubic meters per hour and U.S. gallons per minute.

69 / CONVERT FLOW

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Starting values are illustrative. Use your own costs, rates and assumptions.

INPUT GROUP 01

Flow rate

Check the assumptions before acting on a result.

Read the method and example

YOUR CALCULATION

The same steady volumetric flow in four units.

Liters per minute (L/min)

100

Cubic meters per hour (m³/h)

6

U.S. liquid gallons per minute

26.417

Liters per second (L/s)

1.667

Keep the calculation

Saving is optional and stays on this device. Unsaved edits are not kept when you leave. CSV includes every input and the current results.

Illustrative inputs loaded. Replace them with your own assumptions.

Need velocity from your flow rate?

A flow conversion keeps the same volume per time. To find mean speed in a full circular pipe, you also need its actual internal diameter. Calculate pipe velocity from flow and internal diameter.

How the water flow unit conversion calculator works

Flow is volume divided by time. The tool first expresses the entered rate in liters per minute, then converts to each other target unit. There are 60 seconds in a minute, 60 minutes in an hour, and 1,000 liters in a cubic meter.

The gallon is the U.S. liquid gallon at 3.785411784 liters. Imperial gallons and dry gallons differ. All target rates describe the same volumetric flow at the same physical conditions; no density or mass flow is inferred.

A converted rate is not a pump selection or pipe-sizing result. Pressure, pipe diameter, friction, elevation, fluid properties and operating limits are outside the model. Standard gas flow conventions are also outside this liquid-volume conversion.

Worked example

100 L/min equals 6 m³/h, approximately 26.417 U.S. gallons per minute, or 1.667 L/s. Entering 6 with cubic meters per hour selected returns 100 L/min.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

  • Pipe Flow Velocity

    Calculate pipe velocity from flow rate and actual internal diameter. Enter L/s, L/min, m³/h or U.S. gpm with mm or inches, and see mean velocity in m/s and ft/s.

  • Tank Fill & Drain Time

    Calculate ideal inventory-change time from simultaneous constant inflow and outflow.

  • Pump Hydraulic Power

    Hydraulic kW = fluid density × standard gravity 9.80665 m/s² × flow in m³/s × differential head in metres ÷ 1,000.

  • Liquid Mass & Volume

    Estimate liquid mass from volume, or volume from mass, using your entered density. See liters, cubic meters, kilograms, tonnes and pounds together.

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