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Litersper Minute Calculator

Estimate litersper minute for your project with our free calculator. Get accurate material quantities, costs, and specifications.

Reviewed by Abdullah, Technical Content Specialist

Reviewed by Abdullah, Technical Content Specialist

Formula

LPM = (Liters / Seconds) x 60 | LPM = GPM x 3.78541

For a timed collection, divide the collected volume in liters by the fill time in seconds and multiply by 60 to scale to one minute. For unit conversions, multiply US gallons per minute by 3.78541, or divide cubic meters per hour by 0.06 to get liters per minute.

Worked Examples

Example 1: Container Fill Test

Problem:A 20-liter container fills in 90 seconds from a garden tap. What is the flow rate?

Solution:LPM = (liters / seconds) x 60\nLPM = (20 / 90) x 60 = 13.33 LPM\nGPM = 13.33 / 3.785 = 3.52 GPM

Result:13.33 liters per minute (3.52 GPM)

Example 2: GPM to LPM Conversion

Problem:A pump is rated at 15 GPM. Convert this to liters per minute and cubic meters per hour.

Solution:LPM = 15 x 3.78541 = 56.78 LPM\nCubic m/hr = 56.78 x 0.06 = 3.407 m3/hr\nLiters/hour = 56.78 x 60 = 3,407

Result:56.78 LPM or 3.407 cubic meters per hour

Frequently Asked Questions

How do you calculate liters per minute from a container test?

Fill a container of known volume and record the time it takes. Divide the volume in liters by the fill time in seconds, then multiply by 60 to get liters per minute. For example, if a 10-liter bucket fills in 45 seconds, the flow rate is (10/45) x 60 = 13.33 LPM. For best accuracy, repeat the measurement three times and average the results. This method works for any faucet, hose, or pump outlet.

How do you convert GPM to liters per minute?

Multiply gallons per minute by 3.78541 to get liters per minute, since one US gallon equals 3.78541 liters. For example, 10 GPM equals 37.85 LPM. To convert the other direction, divide liters per minute by 3.78541 to get GPM. Note that imperial gallons (used in the UK) are different from US gallons, with 1 imperial gallon equaling 4.54609 liters.

References

Reviewed by Abdullah, Technical Content Specialist · Editorial policy