Flow Rate converter

Volumetric flow rate measures how much volume moves past a point per unit of time, referenced here to cubic meter per second. Cubic meter per minute, hour, and day scale down as the time unit lengthens, since the same flow spread over a longer period corresponds to a smaller per-second factor. Liter-based units follow the same logic at 1/1000th the volume of a cubic meter. The imperial side — cubic feet, US gallons, UK gallons, oil barrels, and acre-feet — each carry their own volume definition, which is why CFM, GPM, and barrels-per-day all look unrelated to each other and to the metric units at first glance.

The featured conversion is liter per minute to US gallons per minute: GPM = L/min × 0.2641720524. Reverse it by multiplying by 3.785411784.

A garden hose running at 10 L/min converts to 10 × 0.2641720524 ≈ 2.64 GPM. A rooftop HVAC unit moving 400 CFM converts to cubic meters per hour at roughly 400 × 1.699 ≈ 679.6 m³/h, using the ratio between the cubic-foot-per-minute and cubic-meter-per-hour factors.

Flow rate units map directly onto specific industries: GPM dominates US pump, irrigation, and plumbing specifications; CFM is the standard for HVAC ductwork and air-handling equipment; m³/h and L/min are the metric-world defaults for industrial process piping and municipal water systems; barrels per day is the oil industry's production-rate benchmark; and acre-feet per day shows up in agricultural and reservoir water-management planning, where volumes are naturally thought of in terms of flooding a given land area to a given depth.

The sharpest trap in this category is the US gallon versus the UK (imperial) gallon — they're not the same volume, and a UK gallon is about 20% larger, so GPM and gal uk/min give meaningfully different results for the same physical flow. Always check which gallon a spec sheet means before converting, especially on equipment sourced from outside the US. It's also worth not confusing volumetric flow (this category) with mass flow rate, since for anything other than water at standard conditions — fuel, slurry, compressed gas — the two track differently once density varies.