Liters per Minute Calculator

What this calculator does

This calculator converts between volume, time, and flow rate in liters per minute (L/min), a common unit for describing water flow, pump output, irrigation systems, and fluid delivery in construction and plumbing work.

The formula

Flow rate is simply volume divided by time: rate (L/min) = volume (L) ÷ time (min). To find fill time instead, the calculator rearranges the same relationship: time (min) = volume (L) ÷ flow rate (L/min). Results are also shown converted to liters per second and US gallons per minute for convenience.

• 1 US gallon equals approximately 3.78541 liters.
• Actual flow rates from pumps or taps can vary with pressure, pipe diameter, and fittings, so treat results as estimates for planning.

This tool is for general planning and educational purposes.