LPM to GPM Converter
Convert litres per minute (LPM) to US gallons per minute (GPM). Divide by 3.78541, or equivalently multiply by 0.264172. This is the conversion you need when sizing US-specified equipment from a metric flow requirement.
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LPM to GPM conversion resultFree download
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How It Works
LPM is the everyday metric flow unit for pumps, taps and small process lines. GPM is what US pump curves, valve Cv tables and plumbing codes are written in. Since both express volume per minute, the conversion depends only on the litre-to-gallon ratio and never on the pipe or the fluid.
LPM to GPM Formula
GPM = LPM × 0.264172
One litres per minute equals 0.264172 US gallons per minute. Going the other way, one US gallons per minute equals 3.78541 litres per minute.
Worked Example
Converting 100 LPM:
100 × 0.264172 = 26.4172 GPM
LPM to GPM Conversion Table
| LPM | GPM |
|---|---|
| 1 LPM | 0.264172 GPM |
| 5 LPM | 1.32086 GPM |
| 10 LPM | 2.64172 GPM |
| 25 LPM | 6.6043 GPM |
| 50 LPM | 13.2086 GPM |
| 100 LPM | 26.4172 GPM |
| 250 LPM | 66.043 GPM |
| 500 LPM | 132.086 GPM |
| 1000 LPM | 264.172 GPM |
Going the other way? Use the GPM to LPM converter. For any other unit pair, the full flow rate converter handles all ten supported units.
FAQ
Common questions about converting litres per minute to US gallons per minute.
Frequently Asked Questions
How do I convert LPM to GPM?
Multiply the LPM value by 0.264172, or divide it by 3.78541. For example, 100 LPM x 0.264172 = 26.4172 GPM.
How many GPM is 1 litre per minute?
One litre per minute equals 0.264172 US gallons per minute. Put the other way round, it takes roughly 3.79 LPM to make 1 GPM.
What is 100 LPM in GPM?
100 LPM equals 26.4172 GPM. A useful field approximation is to divide litres per minute by 4 and add about 6%.
Should I convert to US or Imperial gallons?
US gallons unless the source explicitly says Imperial. One Imperial gallon is 4.54609 litres, so 100 LPM is 21.9969 Imperial GPM rather than 26.4172 US GPM — a 20% difference that matters when sizing pumps.
Is LPM the same as L/min?
Yes. LPM, L/min and lpm are all the same unit, litres per minute. The abbreviation varies by manufacturer but the quantity is identical.
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