What Is Liters per Second to GPM Conversion?
Flow rate measures how much fluid moves past a point per unit of time. In metric countries it is commonly expressed in liters per second (L/s), while in the United States it is often given in gallons per minute (GPM). This converter translates a flow rate from L/s into US GPM, which is the standard used for pumps, plumbing, irrigation, and HVAC specifications in the US.
How to Use This Converter
Enter your flow rate in liters per second and the calculator instantly shows the equivalent value in US gallons per minute. It is useful when reading a pump curve labeled in metric units but sizing equipment rated in GPM, or vice versa.
The Formula Explained
One liter per second equals 15.8503 US gallons per minute. This comes from the fact that one US gallon is 3.785411784 liters and one minute is 60 seconds: \(60 \div 3.785411784 \approx 15.8503\). So the conversion is simply:
$$\text{GPM} = \text{L/s} \times 15.8503$$
Worked Example
Suppose a pump delivers 2.5 L/s. Multiply by the factor: $$2.5 \times 15.8503 = 39.62575 \text{ GPM}$$ The pump moves about 39.6 US gallons every minute.
FAQ
Is this US or Imperial gallons? This converter uses US gallons. If you need Imperial (UK) gallons per minute, the factor is about 13.198 instead.
Why 15.8503 and not a round number? Because the gallon and liter are defined independently, the conversion factor is an irrational-looking decimal derived from exact definitions.
How do I convert GPM back to L/s? Divide the GPM value by 15.8503 to get liters per second.
