Convert L/min to m³/h litres per minute ↔ cubic metres per hour Free Online Secure
Type a value in litres per minute and read it in cubic metres per hour 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 m³/h (litres per minute ↔ cubic metres per hour)
| L/min | m³/h |
|---|---|
| 1 | 0.06 |
| 2 | 0.12 |
| 3 | 0.18 |
| 5 | 0.3 |
| 10 | 0.6 |
| 20 | 1.2 |
| 50 | 3 |
| 100 | 6 |
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 cubic metres per hour: from pilot plant to full-scale process
Process engineers work at two scales. The laboratory bench and the pilot plant run in litres per minute, because the flows are small and the numbers are convenient. The full-scale plant, its pumps and its flow meters run in cubic metres per hour, because the flows are large. Moving a design from one to the other means turning L/min into m³/h again and again. To convert L/min to m³/h, multiply by 0.06: 10 L/min is 0.6 m³/h, 100 L/min is 6 m³/h and 1,000 L/min is 60 m³/h. The calculator above multiplies as you type, and the sections below show how the numbers behave in filtration, desalination, cooling circuits and pipe sizing.
The page gives the rule with worked examples, a profile of each unit, a comparison and a long run of process and utility cases, followed by the usual slips. The calculation runs in your browser and nothing you type is sent anywhere. Safety-critical sizing should be checked by a qualified engineer.
How to convert L/min to m³/h: multiply by 0.06
The rule
One cubic metre is 1,000 litres and one hour is 60 minutes, so a flow of one litre per minute is 60 litres an hour, which is 0.06 cubic metres an hour. To convert L/min to m³/h, multiply the L/min by 0.06: 25 L/min gives 1.5 m³/h, 140 L/min gives 8.4 m³/h and 700 L/min gives 42 m³/h. To go back, multiply m³/h by 16.67.
Worked examples
A laboratory chiller circulating 15 L/min moves 0.9 m³/h. A reverse-osmosis feed of 50 L/min is 3 m³/h. A dewatering pump of 1,000 L/min is 60 m³/h. A dosing pump of 5 mL/min is only 0.0003 m³/h.
Why the factor is exact
The factor 0.06 follows from the definitions of the litre, the cubic metre and the hour, so nothing is rounded inside it. Every metric country uses the same figure, which cannot be said of the gallon.
A quick sanity test
The answer in m³/h is about a seventeenth of the L/min figure. If a “convert L/min to m³/h” calculation gave a larger number than you started with, you multiplied by 16.67 instead of 0.06.
Litres per minute
The bench-scale unit
Litres per minute are the working units of laboratories, small plants, pumps for the home and small flow meters. The figures are small whole numbers, which suits instruments with analogue scales.
Where it appears
Laboratories, pilot plants, small pumps and domestic appliances.
Cubic metres per hour
The plant-scale unit
Cubic metres per hour are the working units of pumps, flow meters, filtration systems and utility networks. Pump curves, meter ratings and design reports for plants use them because the numbers stay compact at large flows.
Where it appears
Pump catalogues, water and wastewater plants, process lines and building services.
L/min against m³/h
One L/min is 0.06 m³/h, so the figure in m³/h is about seventeen times smaller. 60 L/min is 3.6 m³/h and 300 L/min is 18 m³/h. They measure the same flow; only the scale differs.
The conversion is exact. The commonest trap is mixing litres per minute with litres per hour or per second, which differ by factors of 60.
Where the conversion shows up
Scaling up a process
A pilot filter that treats 10 L/min, 0.6 m³/h, is scaled by a factor of 100 to handle 1,000 L/min, 60 m³/h. The area of the full-scale filter grows by the same factor while the loading per square metre stays constant. A “convert L/min to m³/h” calculation is the first line in the scale-up table.
Desalination
A small reverse-osmosis plant taking in 50 L/min, 3 m³/h, with 75 per cent recovery, makes 37.5 L/min of permeate, 2.25 m³/h or 54 m³ a day. The reject stream is 12.5 L/min, 0.75 m³/h. Membrane vendors quote permeate in m³/day, and pumps are bought in m³/h.
Cooling circuits
A cooling circuit of 100 L/min, 6 m³/h, with a 5 K temperature rise carries away 34.9 kW. The same load at a 10 K rise needs only 50 L/min, 3 m³/h. Halving the flow halves the pumping and pipe size, but the return water is warmer.
Sizing pipes by velocity
At a typical design speed of 1.5 m/s, a DN25 pipe carries 44 L/min, 2.65 m³/h, a DN50 pipe 177 L/min, 10.6 m³/h, and a DN100 pipe 707 L/min, 42.4 m³/h. Flow grows with the square of the diameter, so doubling the pipe size quadruples the capacity at the same speed.
Greenhouse fertigation
A greenhouse irrigation zone takes 30 L/min, 1.8 m³/h. A system of ten zones served in turn needs a pump of at least 1.8 m³/h, but a pump of 6 m³/h allows three zones at once. The fertiliser injector is sized at a percentage of the main flow, as with any dosing.
Brewing and food
A brewery wort transfer of 200 L/min, 12 m³/h, moves a 2,000 litre batch in 10 minutes. Food-grade pumps have flow ranges in m³/h, and hygienic piping is chosen so that the velocity stays under 2 m/s. A process line of 12 m³/h calls for a tube of DN50.
Heat transfer
A heat exchanger duty is flow times specific heat times temperature change. With 200 L/min, 12 m³/h, of water cooled by 10 K, the duty is 140 kW. The same duty at 50 L/min, 3 m³/h, needs a 40 K change. Designers pick the flow to balance pumping cost against exchanger size.
Hydraulic oil circuits
A machine tool hydraulic unit delivers 40 L/min, 2.4 m³/h, at 160 bar. The hydraulic power is flow times pressure, 10.7 kW. Pump catalogues quote displacement in cm³ per revolution, and the flow follows from the speed, so a 20 cm³ pump at 2,000 rpm gives 40 L/min.
Boiler feed and condensate
A boiler making 1 tonne of steam an hour needs 1 m³/h of feedwater, 16.7 L/min. For a plant of 10 tonnes an hour the feed is 10 m³/h, 167 L/min. Condensate returns lower the make-up flow, which is why the make-up meter reads far less than the feed pump.
Fire protection tests
Fire pumps are tested at 100 per cent and 150 per cent of rated flow. A pump of 2,400 L/min, 144 m³/h, is tested at 3,600 L/min, 216 m³/h, and must still give 65 per cent of rated head. A test report in L/min and m³/h should show both units side by side.
A worked example
A pilot UV unit treats 25 L/min, 1.5 m³/h. The full-scale unit must treat 90 m³/h, so the scale factor is 60 and the flow is 1,500 L/min. If the pilot dose was 40 mJ/cm², the large unit needs the same dose, which means about 60 times more lamp power.
The mental shortcut
To convert L/min to m³/h in your head, multiply by 6 and move the decimal point two places to the left. For 250 L/min: 250 × 6 = 1,500, which becomes 15 m³/h. The method is exact because 0.06 is simply 6 divided by 100.
Spreadsheet formulas
In a spreadsheet, keep the L/min in column A and use =A2*0.06 in column B. The reverse is =B2/0.06. A column that multiplies L/min by 60 gives L/h, and one that divides by 60 gives L/s, so the three scales sit side by side.
Rounding in plant reports
Flow meter readings carry about 1 per cent uncertainty, so quote m³/h to three significant figures. 140 L/min is 8.4 m³/h, not 8.40000. Reports that cite the same stream in two units should round both consistently.
Pump curves
A pump catalogue shows flow in m³/h on the horizontal axis and head in metres on the vertical one. A pump of 6 m³/h, 100 L/min, at 20 m head has hydraulic power of 327 W. At an efficiency of 50 per cent the shaft needs 654 W. A “convert L/min to m³/h” calculation puts a bench pump on the catalogue axis.
Landmarks to memorise
1 L/min is 0.06 m³/h. 5 L/min is 0.3 m³/h. 25 L/min is 1.5 m³/h. 100 L/min is 6 m³/h. 250 L/min is 15 m³/h. 1,000 L/min is 60 m³/h. With these landmarks nearly every mental convert L/min to m³/h is possible.
Reference ladder
2 L/min: 0.12 m³/h. 12 L/min: 0.72 m³/h. 45 L/min: 2.7 m³/h. 130 L/min: 7.8 m³/h. 320 L/min: 19.2 m³/h. 800 L/min: 48 m³/h. 1,500 L/min: 90 m³/h. A table like this lets you test a calculator output at a glance.
Checking by reversing
To check a “convert L/min to m³/h” calculation result, divide the answer by 0.06, or multiply by 16.67. If 45 L/min gave 2.7 m³/h, then 2.7 × 16.67 = 45.0. A second test is size: the m³/h figure must be about a seventeenth of the L/min one.
Link to litres per second and gallons per minute
One L/min is 1/60 L/s, 60 L/h, 0.06 m³/h and 0.2642 US gal/min. A flow of 180 L/min is 3 L/s, 10.8 m³/h and 47.6 gal/min. These express the same flow, and a “convert L/min to m³/h” calculation just swaps the label.
Two routes to one answer
You can multiply by 0.06 straight, or go through litres per hour: L/min × 60 / 1,000. A third route uses litres per second, L/min / 60 × 3.6. If the routes disagree, a digit was copied wrongly.
Clean-in-place circuits
Dairies and breweries clean their pipes by recirculating hot detergent at a velocity of at least 1.5 m/s to keep the flow turbulent. In a DN50 line that is 10.6 m³/h, 177 L/min. A “convert L/min to m³/h” calculation on the CIP pump rating tells whether a small skid can reach that speed in the pipework it serves.
Ultrapure water loops
A laboratory ultrapure water loop circulates 2 L/min, 0.12 m³/h, to keep the water moving and the resistivity high. A semiconductor plant circulates 100 m³/h, 1,667 L/min. Both are kept above a minimum velocity in the pipe to discourage bacteria, so the flow is set by the line size, not by demand.
Solar thermal collectors
A solar collector field is usually run at 1 to 2 L/min per square metre of collector. A field of 20 m² therefore needs 20 to 40 L/min, which is 1.2 to 2.4 m³/h. A lower flow raises the outlet temperature but lowers the efficiency, and the circulation pump is picked from a table in m³/h.
Apartment blocks and simultaneity
A shower uses 9 L/min, 0.54 m³/h. In a block of 40 flats the design assumes that only about one in five draws water at the same moment, so the peak demand is eight showers, 72 L/min, 4.3 m³/h. Sizing for all 40 at once would give 21.6 m³/h and a pipe more than twice the diameter that is needed.
Chemical dosing
Dosing is usually a fixed fraction of the main flow. For 0.1 per cent in a stream of 3 m³/h, 50 L/min, the dosing pump must deliver 3 L/h, which is 50 mL/min. A dosing pump with a range of 0 to 10 L/h therefore sits at 30 per cent of its stroke, a comfortable point for accuracy.
Sand filters
A sand filter 600 mm in diameter has an area of 0.283 m². At a filtration velocity of 30 m/h it passes 8.5 m³/h, 141 L/min. A filter loaded at 50 m/h passes 14 m³/h, 236 L/min, but cleans less thoroughly. The vendor's flow rating is a ceiling, not a target.
Swimming pool turnover
A residential pool of 33.6 m³ with a pump flow of 140 L/min, 8.4 m³/h, turns over in 4 hours. A public pool must turn over in 2 to 4 hours, so a 300 m³ pool needs 75 to 150 m³/h, which is 1,250 to 2,500 L/min.
Water softeners
A softener sized for a service flow of 40 L/min, 2.4 m³/h, serves a house with two bathrooms. Larger units handle 100 L/min, 6 m³/h. If flow goes above the rated service flow, hardness leaks through, so the peak of the building matters more than the daily average.
Wastewater and dewatering
A small sewage pumping station of 20 L/s moves 1,200 L/min, 72 m³/h. A trash pump on a building site gives 1,000 L/min, 60 m³/h. Dewatering a pit of 300 m³ at that rate takes five hours, but groundwater inflow can keep the pump running much longer.
Flow meters and turndown
Every flow meter has a usable range. A meter reading from 0.5 to 15 m³/h covers 8.3 to 250 L/min, a turndown of 30 to 1. Below the minimum the reading is unreliable, and above the maximum the meter is damaged or loses accuracy. Convert the range before comparing with a bench instrument in L/min.
Pharmaceutical and fine chemical lines
A chromatography column runs at 100 mL/min, 0.1 L/min, which is only 0.006 m³/h. A production column of 100 times the volume runs at 10 L/min, 0.6 m³/h. The scale-up preserves the linear velocity, so flow goes up with the cross-sectional area, and a “convert L/min to m³/h” calculation is used at each stage.
More values for convert L/min to m³/h
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 = 0.006 m³/h
- 0.5 L/min = 0.03 m³/h
- 3 L/min = 0.18 m³/h
- 4 L/min = 0.24 m³/h
- 7 L/min = 0.42 m³/h
- 15 L/min = 0.9 m³/h
- 20 L/min = 1.2 m³/h
- 75 L/min = 4.5 m³/h
- 200 L/min = 12 m³/h
- 500 L/min = 30 m³/h
- 2,000 L/min = 120 m³/h
- 10,000 L/min = 600 m³/h
Common slips with a “convert L/min to m³/h” calculation
Multiplying by 16.67
Going from L/min to m³/h makes the figure smaller. If 100 L/min became 1,667, you used the factor for the other direction.
Minutes, hours and seconds
L/h to m³/h means dividing by 1,000, L/min to m³/h multiplying by 0.06, and L/s to m³/h multiplying by 3.6. Check the time unit before applying a factor.
Rated against actual flow
A pump's rated flow applies at one head. In a real system the flow is where the pump curve meets the system curve, usually lower. Use measured flow when you size downstream equipment.
Short answers
How do I convert L/min to m³/h?
Multiply the litres per minute by 0.06.
How many m³/h is 100 L/min?
6 m³/h.
How many m³/h is 1,000 L/min?
60 m³/h.
How many L/min is 1 m³/h?
16.67 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 gal/min, Convert km to mi, Convert mi to km, Convert °C to °F, Convert °F to °C, Convert hp to W, Convert cm³ to m³, Convert mph to ft/s, Convert °C to °Ré. For the opposite direction see Convert m³/h to L/min.
In short, a “convert L/min to m³/h” calculation means one multiplication by 0.06 and a unit written next to the result. Your figure is calculated locally, with no account and no upload.