GPM to LPM & LPM to GPM Calculator
Convert US Gallons per Minute (GPM) to Liters per Minute (LPM) instantly. Size pumps, analyze piping systems, and calculate water flow rates using our engineering-grade tool.
How to Use GPM to LPM Calculator
Converting volumetric flow rate values from gallons per minute to liters per minute is simple using our responsive layout. Sizing fluid mechanics systems, choosing booster pumps, and verifying flow dynamics require accurate conversions. Follow this professional workflow to obtain verified flow results:
- 1Enter the flow rate in gallons per minute. Input the flow rate in the input field.
- 2Click Calculate. Click the Calculate Flow button to run the conversion.
- 3View the equivalent flow rate in liters per minute. The converted values will display in the output cards for liters per minute, liters per second (L/s), and cubic meters per hour (m³/hr).
- 4Use the result for pump selection or flow analysis. Apply these values for centrifugal pump sizing, irrigation design, and piping calculations.
How to Calculate GPM to LPM
Converting flow rates between US gallons per minute (GPM) and liters per minute (LPM) requires using the precise physical relationship between gallons and liters. These mathematical relations are derived from the physical definitions of volumetric measurements. Follow this standard conversion formula:
Step-by-Step Practical Example
Convert a water pump flow rate of 25 GPM into liters per minute:
Step 1: Apply the conversion factor.
Step 2: Compute the result.
Final Answer:
25 GPM = 94.64 LPM (rounded to two decimal places).
Where is GPM to LPM Conversion Used?
Fluid dynamics conversions are essential in several engineering applications:
- Water pumps: Sizing commercial, residential, and agricultural water pumps.
- Irrigation systems: Configuring sprinkler networks and drip pipelines.
- Industrial process equipment: Managing dosing pumps and chemical lines.
- Hydraulic systems: Sizing control valves, cylinders, and fluid reservoirs.
GPM to LPM Chart
This reference chart displays conversions from US gallons per minute (GPM) to liters per minute (LPM). All values are calculated using the standard US gallon conversion factor of 3.78541 and are rounded to two decimal places.
| Flow Rate (GPM) | Liters per Minute (LPM) |
|---|---|
| 1 GPM | 3.79 LPM |
| 2 GPM | 7.57 LPM |
| 5 GPM | 18.93 LPM |
| 10 GPM | 37.85 LPM |
| 15 GPM | 56.78 LPM |
| 20 GPM | 75.71 LPM |
| 25 GPM | 94.64 LPM |
| 30 GPM | 113.56 LPM |
| 40 GPM | 151.42 LPM |
| 50 GPM | 189.27 LPM |
| 75 GPM | 283.91 LPM |
| 100 GPM | 378.54 LPM |
Note: Values are based on the standard conversion factor of 1 US gallon per minute = 3.78541 liters per minute.
How to Convert LPM to GPM
Divide litres per minute by 3.78541 to get US gallons per minute, or by 4.54609 for Imperial (UK) gallons per minute.
Example: a pump that delivers 38 L/min moves 38 ÷ 3.78541 = 10.04 US GPM.
| Flow (LPM) | US GPM | Imperial GPM |
|---|---|---|
| 5 | 1.32 | 1.10 |
| 10 | 2.64 | 2.20 |
| 20 | 5.28 | 4.40 |
| 38 | 10.04 | 8.36 |
| 50 | 13.21 | 11.00 |
| 100 | 26.42 | 22.00 |
| 200 | 52.83 | 43.99 |
Frequently Asked Questions (FAQs)
To convert US gallons per minute (GPM) to liters per minute (LPM), you simply multiply the GPM value by 3.78541. This conversion factor accounts for the fact that one US liquid gallon is exactly equal to 3.78541 liters in the metric system.
The standard multiplier used to convert US GPM to LPM is 3.78541. If you are working with UK Imperial gallons per minute, the multiplier is different, at approximately 4.54609 liters per Imperial gallon, so always check the gallon type.
To find the equivalent of 10 US gallons per minute in liters per minute, you multiply 10 by the conversion factor of 3.78541. The result is 37.8541 LPM. This metric is frequently used for specifying pump capacities in international markets.
GPM is the standard unit for measuring volumetric flow rate in the United States, while LPM is used internationally in countries that follow the metric system. Offering both measurements ensures compatibility across different global industries.
Yes, there is a significant difference. One US GPM equals 3.785 LPM, while one Imperial GPM equals 4.546 LPM. It is crucial to know which type of gallon you are measuring to ensure your conversion to liters per minute is entirely accurate.
The formula to convert liters per minute to US gallons per minute is: GPM = LPM / 3.78541. Alternatively, you can multiply the LPM value by 0.264172. This mathematical relationship allows for quick conversions when sizing pumps and fluid transport systems.
