Convert L/min to gal/min litres per minute ↔ US gallons per minute Free Online Secure
Type a value in litres per minute and read it in US gallons per minute at once. The factor is exact by definition, the arithmetic happens in your browser, and nothing is sent anywhere.
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Convert from litres per minute
Common values — Convert L/min to gal/min (litres per minute ↔ US gallons per minute)
| L/min | gal/min |
|---|---|
| 1 | 0.264172052358 |
| 2 | 0.528344104716 |
| 3 | 0.792516157074 |
| 5 | 1.32086026179 |
| 10 | 2.64172052358 |
| 20 | 5.28344104716 |
| 50 | 13.2086026179 |
| 100 | 26.4172052358 |
Where these units come from
Flow rate has no unit of its own either: it is a volume divided by a time, so each trade kept the volume it already used and attached whichever time suited the scale of the job. Litres per minute came from taps, pumps and anything a person watches fill; cubic metres per hour from water utilities, ventilation and irrigation, where a minute is too short to be useful; US gallons per minute from American plumbing, fire codes and well pumps. The numbers look very different for the same stream — one litre per minute is 0.06 cubic metres per hour — which is why a pump quoted in one unit and a pipe sized in another is a common source of expensive mistakes.
Where you meet them
A shower head delivers around 9 litres per minute, a garden hose roughly twice that, a domestic boiler is rated by how many litres a minute it can raise by a given temperature. Cubic metres per hour price water, size ventilation ducts and rate industrial pumps. Gallons per minute appear on American pump labels, sprinkler systems and fire hydrant specifications.
Questions people ask
Which gallon does gallons per minute mean here?
The US gallon, 3.785411784 litres. An imperial gallon per minute would be about a fifth larger, so a British figure quoted in gpm and read as American understates the flow by about a sixth. Pump and sprinkler data sheets rarely say which they mean, so check the country of origin before trusting a conversion in either direction.
Is a higher flow rate the same as higher pressure?
No, and confusing them is how showers get ruined. Pressure is the push; flow is how much actually moves. A narrow pipe at high pressure can deliver less water than a wide pipe at low pressure. Pumps are specified by both together — a curve showing what flow they achieve at each pressure — because neither number means much on its own.
Is the answer exact?
Where both units are defined in terms of one another by whole numbers, yes — the page says so above the figure, and the only rounding is in how many digits are shown. Where the ratio has no finite decimal, the page shows twelve significant digits and says the relation is approximate rather than pretending otherwise.
Does anything I type leave my device?
No. The arithmetic runs in your browser; nothing is uploaded and there is no server to upload it to. Load the page once and it keeps working with the network switched off.
Litres per minute to gallons per minute: pumps, sprinklers and hydraulics bought in two systems
A pump from a European factory is rated in litres per minute, and the same pump sold in the United States is rated in gallons per minute. Fire-protection tables, irrigation catalogues, well drillers and hydraulic suppliers all work in gpm, so an engineer, a farmer or a boat owner outside America regularly has to turn L/min into gal/min before choosing a part. To convert L/min to gal/min, multiply by 0.2642: 10 L/min is 2.64 gal/min, 100 L/min is 26.4 gal/min and 1,000 L/min is 264 gal/min. The gallon here is the US gallon of 3.785 litres. The calculator above multiplies as you type, and the sections below show what the figures mean in fire protection, irrigation, hydraulics and well work.
The page gives the rule with worked examples, a profile of each unit, a comparison and a long run of engineering and farm cases, followed by the usual slips. The calculation runs in your browser and nothing you type is sent anywhere. Safety systems must be designed to the standards of the place where they are installed.
How to convert L/min to gal/min: multiply by 0.2642
The rule
One US gallon is 3.785412 litres, so one litre per minute is 0.264172 gal/min. To convert L/min to gal/min, multiply the L/min by 0.2642: 8 L/min gives 2.11 gal/min, 60 L/min gives 15.9 gal/min and 400 L/min gives 105.7 gal/min. To go the other way, multiply gal/min by 3.785.
US and imperial gallons
A British gallon is 4.546 litres, so the same flow of 100 L/min is 26.4 US gal/min but 22.0 imperial gal/min. Equipment sold in North America uses the US gallon, and this page does too. Older British pump data and some Commonwealth sources use the imperial one.
Worked examples
A hydraulic pump of 40 L/min delivers 10.6 gal/min. A garden pump of 95 L/min delivers 25 gal/min. A fire pump of 5,678 L/min delivers 1,500 gal/min, the standard rating of an American pumper.
A quick sanity test
The answer in gal/min is about a quarter of the L/min figure. If a “convert L/min to gal/min” calculation gave a larger number than you started with, you multiplied by 3.785 instead of 0.2642.
Litres per minute
The metric working unit
The litre per minute is how small and medium flows are stated in most of the world. It sits between the litre per second used in fire and water-supply design and the cubic metre per hour used on large pumps.
Where it appears
Pumps, valves, heaters, dosing equipment and laboratory apparatus.
Gallons per minute
The American flow unit
The gallon per minute, gpm, is the standard flow rate in the United States. Plumbing codes, fire standards, well logs and pump curves are all written in it, usually with head in feet and pressure in psi.
Where it appears
American catalogues, codes and equipment manuals.
L/min against gal/min
One L/min is 0.2642 gal/min, so the figure in gal/min is nearly four times smaller. 20 L/min is 5.28 gal/min and 500 L/min is 132 gal/min. They measure the same flow; only the scale differs.
The conversion is exact. The commonest trap is confusing the US gallon with the imperial gallon, which differ by 20 per cent.
Where the conversion shows up
Fire protection
American fire-fighting figures are in gpm: a handline of 150 gpm is 568 L/min, a 2.5-inch line at 250 gpm 946 L/min, a master stream of 1,000 gpm 3,785 L/min and a pumper rated 1,500 gpm 5,678 L/min. A sprinkler flows Q = K√P. With K = 5.6 gpm/psi^0.5 at 7 psi it delivers 14.8 gpm, 56 L/min, which in metric terms is K = 80 L/min/bar^0.5 at 0.5 bar. A “convert L/min to gal/min” calculation links the two sets of tables.
Irrigation
A centre pivot of 800 gpm, 3,028 L/min, delivers 181.7 cubic metres an hour. It applies 25 mm over 1 hectare in 1.4 hours, so over a 50-hectare circle it takes about 69 hours to give 25 mm. Drip emitters run at 1 gph, 63 mL/min, or 4 L/h, 67 mL/min.
Wells
A domestic well of 10 gpm, 37.9 L/min, is a healthy yield. Pumping 20 gpm for 12 hours takes 14,400 gallons, 54.5 cubic metres. A well driller's log gives the yield in gpm, and the pump is chosen for less than that to avoid drawing the well dry.
Hydraulic power from flow and pressure
Hydraulic power is flow times pressure. A pump delivering 40 L/min at 200 bar has 13.3 kW. In US units that is 10.6 gpm at 2,900 psi and 17.9 hp. The formula in US units is hp = gpm × psi / 1,714, which gives 10.6 × 2,900 / 1,714 = 17.9 hp.
Oil and drilling
The oilfield measures flow in barrels per minute, and a barrel is 42 US gallons, 159 litres. A drilling mud pump delivering 500 gpm moves 1,893 L/min, 11.9 barrels per minute. Drilling reports to European partners carry L/min, so a “convert L/min to gal/min” calculation is routine at an operator's office.
Brewing and food
A brewery transfers wort at 5 gpm, 18.9 L/min, so a 20 barrel batch of 2,350 litres takes about two hours. Pumps in dairies run at 20 to 100 gpm, 76 to 379 L/min. Food-grade sanitary pumps in the US are sold in gpm and must be matched to European piping that is specified in L/min.
Water treatment
A softener sized for 10 gpm is 37.9 L/min, which is enough for the peak of a typical home. A reverse-osmosis unit for drinking water makes 50 gallons a day, 189 litres, or 0.13 L/min on average. Backwash flows of a filter are higher: 15 gpm, 56.8 L/min, for a typical household tank.
Swimming pools
A pool pump of 60 gpm, 227 L/min, moves 13.6 cubic metres an hour. For a pool of 60 cubic metres that turns the water over in 4.4 hours. Sand filters have a maximum flow in gpm per square foot, usually 15, which equals 36.7 m³/h per square metre.
Cooling water
A chiller with a 50 kW load and a 5 K rise needs 143 L/min, 37.9 gal/min, of water. In US units the rule of thumb is gpm = 24 × tons / rise in °F. A 50 kW load is 14.2 tons, and a 5 K rise is 9 °F, so 24 × 14.2 / 9 = 37.9 gpm. The L/min and gpm tables give the same answer for the same load.
Showers and faucets
Federal US limits are 2.5 gpm for showerheads and 2.2 gpm for faucets, equal to 9.46 and 8.33 L/min. WaterSense labelled fittings flow 2.0 gpm, 7.57 L/min, and 1.5 gpm, 5.68 L/min. A European product at 8 L/min, 2.11 gpm, passes the federal shower limit comfortably.
Laboratory and medical equipment
A lab chiller circulating 8 L/min, 2.1 gpm, cools an instrument. A hemodialysis machine runs dialysate at 500 mL/min, 0.13 gpm. Medical gases such as oxygen are in L/min too, but gas, not liquid, so they have no gallon equivalent on this page.
A worked example
You must replace a European pump delivering 300 L/min at 40 metres with an American one. 300 L/min is 79.3 gpm, and 40 m is 131 ft. Look in the catalogue for a pump that gives at least 80 gpm at 131 ft of head, and check the motor frequency of 60 Hz, which changes the speed and flow on a 50 Hz supply.
The mental shortcut
To convert L/min to gal/min in your head, divide by 3.8. For 150 L/min: 150 / 3.8 = 39.5 gpm, against the exact 39.6. The slip is 0.4 per cent. Dividing by 4 is quicker but gives 37.5, which is 5 per cent low.
Spreadsheet formulas
In a spreadsheet, keep the L/min in column A and use =A2*0.264172 in column B. The reverse is =B2*3.785412. A column that multiplies L/min by 0.06 gives m³/h and offers a quick cross-check.
Tractors and skid steers
A tractor's auxiliary hydraulics give 40 to 60 L/min, 10.6 to 15.9 gal/min. A skid steer loader's standard flow of 20 gpm is 75.7 L/min and its high-flow option of 35 to 40 gpm is 132 to 151 L/min. Attachments such as mulchers carry a minimum flow in gpm that must be matched.
Rounding on data sheets
Pump ratings are rounded to 1 or 5 gpm, and tolerance is typically 5 to 10 per cent. 150 L/min is 39.6 gpm, usually quoted as 40. Do not write 39.6258 gpm; the extra digits imply precision that the pump does not have.
Landmarks to memorise
1 L/min is 0.264 gal/min. 4 L/min is 1.06 gal/min. 10 L/min is 2.64 gal/min. 38 L/min is 10 gal/min. 100 L/min is 26.4 gal/min. 1,000 L/min is 264 gal/min. With these landmarks nearly every mental convert L/min to gal/min is possible.
Reference ladder
2 L/min: 0.53 gal/min. 6 L/min: 1.59 gal/min. 18 L/min: 4.76 gal/min. 35 L/min: 9.25 gal/min. 80 L/min: 21.1 gal/min. 300 L/min: 79.3 gal/min. 750 L/min: 198 gal/min. A table like this lets you test a calculator output at a glance.
Checking by reversing
To check a “convert L/min to gal/min” calculation result, multiply the answer by 3.785. If 80 L/min gave 21.1 gal/min, then 21.1 × 3.785 = 79.9. A second test is size: the gal/min figure must be about a quarter of the L/min figure.
Link to cubic metres per hour and litres per second
One L/min is 0.06 m³/h, 0.01667 L/s and 0.2642 gal/min. A flow of 300 L/min is 18 m³/h, 5 L/s and 79.3 gal/min. All of these describe the same rate, and a “convert L/min to gal/min” calculation just changes the label.
Two routes to one answer
You can multiply by 0.2642 straight, or go through litres: L/min divided by 3.785. A third route uses cubic metres per hour: m³/h × 4.403. If the routes disagree, a digit was copied wrongly.
Petrol and diesel pumps
In the United States the flow from a petrol nozzle is limited to 10 gpm, 37.9 L/min, by regulation. A tank of 15 gallons, 56.8 litres, therefore fills in about 90 seconds. European passenger-car nozzles flow up to 50 L/min, 13.2 gpm, and truck diesel pumps up to 130 L/min, 34 gpm. A “convert L/min to gal/min” calculation explains why a European car fills faster.
Commercial kitchens
Federal rules in the United States cap a pre-rinse spray valve at 1.6 gpm, 6.06 L/min, and the ENERGY STAR level is 1.28 gpm, 4.85 L/min. A restaurant with a pre-rinse in use for three hours a day at 1.6 gpm uses 1,090 litres a day, against 873 litres at 1.28 gpm, a saving of 217 litres daily.
Pumpers and hydrants
A pumper rated 1,500 gpm moves 5,678 L/min at 150 psi, 10.3 bar. A hydrant flowing 1,000 gpm, 3,785 L/min, can supply four 250 gpm lines at once. European fire pumps are rated in L/min or in L/s, with 1,000 L/min the common benchmark for a portable pump.
Sprinkler K-factors
An American sprinkler head has a K-factor in gpm/psi^0.5, commonly 5.6, 8.0 or 11.2, which are 80, 115 and 161 in L/min/bar^0.5. At 20 psi, a K 5.6 head flows 25 gpm, 94.7 L/min. At 50 psi a K 11.2 head flows 79 gpm, 299 L/min. A “convert L/min to gal/min” calculation on each point on the curve produces the metric table.
Centre pivot and field irrigation
A centre pivot with 800 gpm covers about 130 acres, 52.6 hectares. One acre-inch needs 27,154 gallons, which is 25.4 mm over 4,047 square metres. At 800 gpm that takes 34 minutes, so a full pass of 1 inch over the field takes about 74 hours.
Drip systems
A drip emitter of 2 gph is 126 mL/min, 0.033 gal/min. A line of 100 emitters uses 12.6 L/min, 3.3 gal/min. A garden of 500 emitters needs 63 L/min, 16.7 gal/min, which is within the capacity of a typical 1 hp pump. Matching the zone flow to the supply flow is the main design rule.
Well pumps
A submersible well pump of 10 gpm at 150 ft of head is 37.9 L/min at 45.7 metres. The motor needs roughly 3/4 hp, 560 W. A 20 gpm pump, 75.7 L/min, at the same head needs 1.5 hp. Pump curves in the US show gpm against feet of head, and in Europe L/min against metres.
Boats and bilge pumps
Bilge pumps are rated in gallons per hour at no head: 500 gph is 8.3 gpm, 31.5 L/min, and 2,000 gph is 33 gpm, 126 L/min. At 6 feet of lift the delivery falls by about 30 per cent. The raw-water pump of a diesel engine of 100 hp gives 15 to 25 gpm, 57 to 95 L/min, of cooling.
Watermakers
A marine watermaker makes 1,000 gallons a day, which is 3,785 litres a day or 0.69 gpm. That is 2.6 L/min, to be compared with a boat crew using 100 litres per person per day. Reverse-osmosis membranes pass only a fraction of the water that goes in, so the feed pump flow is several times higher.
More values for convert L/min to gal/min
A longer list of conversions
If the value you need is not in the first list, these further conversions may be close enough to read off directly:
- 0.1 L/min = 0.0264172 gal/min
- 0.5 L/min = 0.132086 gal/min
- 3 L/min = 0.792516 gal/min
- 4 L/min = 1.05669 gal/min
- 7 L/min = 1.8492 gal/min
- 15 L/min = 3.96258 gal/min
- 20 L/min = 5.28344 gal/min
- 75 L/min = 19.8129 gal/min
- 200 L/min = 52.8344 gal/min
- 500 L/min = 132.086 gal/min
- 2,000 L/min = 528.344 gal/min
- 10,000 L/min = 2,641.72 gal/min
Common slips with a “convert L/min to gal/min” calculation
Using the wrong direction
From L/min to gal/min the number gets smaller. If 10 L/min became 38, you used the factor for the other direction.
US and imperial gallons
An imperial gallon is 4.546 litres and a US gallon 3.785. A flow of 100 L/min is 26.4 US gpm or 22.0 imperial gpm, so check which unit a British document uses.
Flow and volume
A flow is a volume per unit of time. A figure of 15 gallons without "per minute" is a volume, and cannot be converted with this page.
Short answers
How do I convert L/min to gal/min?
Multiply the litres per minute by 0.2642.
How many gal/min is 10 L/min?
2.64 gal/min.
How many gal/min is 100 L/min?
26.4 gal/min.
How many L/min is 1 gal/min?
3.785 L/min.
Does my number leave my device?
No, the calculation runs in your browser.
More pages and a wrap-up
For other flow conversions see Convert L/min to m³/h, Convert km to mi, Convert mi to km, Convert °C to °F, Convert °F to °C, Convert yd² to m², Convert °F to K, Convert m² to acres, Convert ft to m. For the opposite direction see Convert gal/min to L/min.
In short, a “convert L/min to gal/min” calculation means one multiplication by 0.2642 and a unit written next to the result. Your figure is calculated locally, with no account and no upload.