GPM to L/h Converter

Convert US gallons per minute (GPM) to litres per hour (L/h). One US gallon is 3.785411784 litres and an hour is 60 minutes, so 1 GPM = 227.125 L/h. L/h is the unit on dosing pumps, water filters, drip irrigation emitters and small fuel systems, where a per-minute figure would be a fraction.

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GPM to L/h conversion result

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How It Works

GPM to L/h is two conversions in one: gallons to litres (x 3.78541) and per minute to per hour (x 60). Multiplying the two factors gives 227.125. Because both units are volumetric, no pipe or fluid data is needed.

GPM to L/h Formula

L/h = GPM × 227.125

One US gallon per minute equals 227.125 litres per hour. Going the other way, one litre per hour equals 0.00440287 US gallons per minute.

Worked Example

Converting 2 GPM:

2 × 227.125 = 454.249 L/h

GPM to L/h Conversion Table

GPM L/h
0.25 GPM 56.7812 L/h
0.5 GPM 113.562 L/h
1 GPM 227.125 L/h
2 GPM 454.249 L/h
5 GPM 1135.62 L/h
10 GPM 2271.25 L/h
25 GPM 5678.12 L/h
50 GPM 11356.2 L/h
100 GPM 22712.5 L/h

Going the other way? Use the L/h to GPM converter. For any other unit pair, the full flow rate converter handles every supported unit.

FAQ

Common questions about converting US gallons per minute to litres per hour.

Frequently Asked Questions

How do I convert GPM to L/h?

Multiply the GPM value by 227.125. For example, 2 GPM x 227.125 = 454.249 L/h. The factor is 3.785411784 litres per US gallon times 60 minutes per hour.

How many litres per hour is 1 GPM?

One US gallon per minute is 227.125 litres per hour, or 3.78541 litres per minute.

What is 0.5 GPM in L/h?

0.5 GPM is 113.562 L/h. Under-sink water filters and reverse osmosis systems are often rated in this range.

How do I convert L/h back to GPM?

Divide by 227.125, or multiply by 0.00440287. 1,000 L/h is 4.40287 GPM.

Is this US or Imperial gallons?

US gallons. For Imperial GPM, multiply by 272.765 instead (4.54609 L x 60). The difference is 20%, so check the source of any UK or Canadian figure.

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