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Flow Rate Converter

Enter a volumetric flow rate in any common unit and see it in all the others instantly: cubic metre per second (m³/s), cubic metre per hour (m³/h), litre per second (L/s), litre per minute (L/min), litre per hour (L/h), millilitre per minute (mL/min), cubic foot per second (ft³/s, the cusec), cubic foot per minute (ft³/min, CFM), US gallon per minute (GPM), US gallon per hour (GPH), imperial gallon per minute and oil barrel per day (bbl/day). The value is converted to m³/s internally and then to every unit using exact definitions, so conversions are precise. Handy for pumps and plumbing (GPM, L/min), HVAC and fans (CFM, m³/h), lab work (mL/min), irrigation (L/h) and oil and gas (bbl/day). Everything is computed locally in your browser.

m³/s

1.6667e-5

m³/h

0.06

L/s

0.01666667

L/min

1

L/h

60

mL/min

1,000

ft³/s (cusec)

0.00058858

ft³/min (CFM)

0.03531467

US gal/min (GPM)

0.26417205

US gal/h (GPH)

15.850323

imp gal/min

0.21996925

bbl/day

9.0573275

How to use

  1. Type a flow rate value.
  2. Pick the unit you entered it in.
  3. Read the value in every other unit and copy whichever you need.

Frequently asked questions

How do I convert GPM to L/min?
Multiply by 3.785411784, since a US liquid gallon is exactly 3.785411784 litres. So 5 GPM = 18.93 L/min, and going back, 1 L/min = 0.2642 GPM. A typical low-flow shower head is 2.5 GPM ≈ 9.46 L/min.
What is CFM in m³/h?
1 ft³/min = 1.699011 m³/h (and 28.3168 L/min). Fan and ventilation ratings use CFM in the US and m³/h in most other countries, so a 400 CFM range hood is about 680 m³/h.
Is a US gallon the same as an imperial gallon?
No. A US liquid gallon is 3.785411784 L and an imperial (UK) gallon is 4.54609 L, so 1 imperial GPM = 1.2009 US GPM. Both are listed separately here — check which one a spec sheet means before converting.
Does this work for air as well as water?
Yes. Volumetric flow is volume per unit time regardless of the fluid, so the same conversions apply to air, water, oil or gas. Note that mass flow (kg/s) also depends on density, so it is a different quantity and is not converted here.

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