Flow Rate Converter
Volumetric flow rate measures the volume of fluid passing a point per unit of time and is fundamental in hydraulics, HVAC, irrigation, and industrial processes. This converter handles the five most common units — liters per second (L/s), liters per minute (L/min), cubic meters per hour (m³/h), US gallons per minute (GPM), and cubic feet per minute (CFM) — using a factor table anchored to L/s as the base unit.
Accurate flow rate conversion is critical when specifying pumps, sizing pipes, or comparing equipment data sheets from different countries that use different unit systems. Simply select the source unit, enter your value, and the result appears instantly in the target unit alongside a full reference table for all supported units.
How it works
All conversions go through L/s as the intermediate base: value_Ls = input × factor_from; result = value_Ls ÷ factor_to. Factors: L/s = 1, L/min = 1/60, m³/h = 1/3.6, US gal/min = 0.06309, ft³/min = 0.47195.
Use cases
- Sizing water pumps and hydraulic systems for engineering projects
- Converting HVAC airflow specifications between CFM and m³/h
- Comparing irrigation flow rates from suppliers using different unit systems
- Verifying industrial flow meter readings across international standards
- Converting pipe flow capacity for plumbing design and building codes
Frequently asked questions
How do you convert GPM to liters per minute?
Multiply US gallons per minute by 3.785 to get liters per minute. This follows from the factor table: 1 US GPM = 0.06309 L/s, and 0.06309 × 60 = 3.785 L/min. For example, a 10 GPM pump delivers about 37.85 L/min.
How do you convert m³/h to L/s?
Divide cubic meters per hour by 3.6 to get liters per second. One cubic meter is 1,000 liters and one hour is 3,600 seconds, so 1 m³/h = 1000 ÷ 3600 = 0.2778 L/s. For example, 18 m³/h equals 5 L/s.
What is CFM and how does it convert to m³/h?
CFM (cubic feet per minute) measures airflow and is the standard unit in US HVAC specifications. One CFM equals 0.47195 L/s, which is 1.699 m³/h — so multiply CFM by about 1.7 to get m³/h. A 400 CFM range hood therefore moves roughly 680 m³/h.
What is volumetric flow rate?
Volumetric flow rate is the volume of fluid passing a point per unit of time, such as liters per second or gallons per minute. It is fundamental for sizing pumps and pipes, specifying HVAC equipment, and designing irrigation systems. It differs from mass flow rate, which measures kilograms per second and depends on the fluid's density.
How many liters per minute is 1 liter per second?
1 L/s equals exactly 60 L/min, since there are 60 seconds in a minute. It also equals 3.6 m³/h, about 15.85 US GPM (1 ÷ 0.06309), and about 2.12 CFM (1 ÷ 0.47195). This converter routes every conversion through L/s as the base unit.