GPM to LPM 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.
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GPM to LPM Calculator
Calculations are standard physical conversions. Real-world pump configurations must account for pipe friction, temperature, and specific gravity.
💡 1 US gallon per minute equals 3.78541 liters per minute. This conversion is commonly used in pump sizing, irrigation systems, hydraulic equipment and water treatment applications.
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:
- Step 1: Enter the flow rate in gallons per minute. Input the flow rate in the input field.
- Step 2: Click Calculate. Click the Calculate Flow button to run the conversion.
- Step 3: View 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).
- Step 4: Use 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.
GPM to LPM Calculator Frequently Asked Questions
To convert GPM (US Gallons per Minute) to LPM (Liters per Minute), you multiply the flow rate in GPM by 3.78541. This conversion factor is based on the physical volume of a single US gallon, which equals exactly 3.785411784 liters.
1 US GPM is equal to exactly 3.78541 liters per minute. This conversion is a standard fluid flow measurement reference used across mechanical engineering, municipal plumbing design, and pump sizing applications.
Converting GPM to LPM is crucial for engineers working internationally or comparing equipment. Flow specifications in North America often use US GPM, whereas European and international manufacturers typically use LPM or cubic meters per hour.
Yes, this calculator is based on US liquid gallons, where 1 US gallon is defined as 3.785411784 liters. If you require Imperial gallon conversions (where 1 Imperial gallon equals 4.54609 liters), a different multiplier must be applied.
Gallons per minute (GPM) is primarily used in the United States and countries adhering to SAE standards. It is standard for measuring water pump output, fire protection system discharge, residential plumbing fixtures, and irrigation flow.
Liters per minute (LPM) is the standard metric unit for volumetric flow rate. It is widely used in metric-based countries for industrial pumps, scientific instruments, medical gas delivery (such as oxygen flow), and household water systems.
Yes, this calculator fully supports decimal input values. For example, if you input a fractional flow rate such as 12.5 GPM, the calculator will accurately compute the result as 47.32 LPM using the standard conversion factor.