Cubic feet per minute (ft³/min) to Litres per minute (l/min) conversion

Understanding Cubic feet per minute to Litres per minute Conversion

Cubic feet per minute (ft3/min) and litres per minute (l/min) are both units of volumetric flow rate, meaning they describe how much volume moves through a system in one minute. Cubic feet per minute is commonly used in U.S. customary and HVAC contexts, while litres per minute is widely used in metric-based engineering, laboratory, medical, and fluid-handling applications.

Converting between these units is useful when comparing equipment specifications, interpreting international technical documents, or matching components that use different measurement systems. It is especially common in ventilation, compressed air, pumps, gas flow, and water distribution work.

Conversion Formula

The verified conversion relationship is:

$$1 \ \text{ft3/min} = 28.316831998815 \ \text{l/min}$$

So, to convert from cubic feet per minute to litres per minute:

$$\text{l/min} = \text{ft3/min} \times 28.316831998815$$

The reverse relationship is:

$$1 \ \text{l/min} = 0.03531468492103 \ \text{ft3/min}$$

Which can also be written as:

$$\text{ft3/min} = \text{l/min} \times 0.03531468492103$$

Step-by-Step Example

Suppose an industrial blower is rated at $12.5 \ \text{ft3/min}$.

Write the formula:

$$\text{l/min} = \text{ft3/min} \times 28.316831998815$$

Substitute the value:

$$\text{l/min} = 12.5 \times 28.316831998815$$

Calculate:

$$\text{l/min} = 353.9603999851875$$

So:

$$12.5 \ \text{ft3/min} = 353.9603999851875 \ \text{l/min}$$

Real-World Examples

• A small ventilation fan moving $5 \ \text{ft3/min}$ of air corresponds to $141.584159994075 \ \text{l/min}$, which may be relevant in enclosed equipment cabinets or electronics cooling.

• A laboratory gas supply with a flow of $2.2 \ \text{ft3/min}$ equals $62.296,?$

• A portable air compressor rated at $8 \ \text{ft3/min}$ delivers $226.53465599052 \ \text{l/min}$, a useful comparison when reviewing metric pneumatic tool requirements.

• A medical or industrial oxygen line flowing at $1.5 \ \text{ft3/min}$ corresponds to $42.4752479982225 \ \text{l/min}$, helping align imperial and metric flow specifications.

• A process exhaust duct carrying $20 \ \text{ft3/min}$ equals $566.3366399763 \ \text{l/min}$, which can appear in equipment datasheets and environmental control documentation.

Interesting Facts

• The litre is a metric unit of volume equal to one cubic decimetre, and it is widely accepted for use with the International System of Units even though the SI base unit for volume is the cubic metre. Source: NIST
• Cubic foot and cubic foot per minute are common in airflow measurement, especially in heating, ventilation, and air-conditioning applications. Source: Wikipedia – Cubic foot

Additional Notes on Usage

Cubic feet per minute is often abbreviated as CFM in engineering documents, product manuals, and HVAC specifications. In many cases, CFM refers specifically to airflow, although mathematically it is simply a volume flow rate unit.

Litres per minute is commonly abbreviated as L/min or l/min. It appears frequently in pump curves, medical gas systems, chemical dosing equipment, filtration systems, and laboratory instruments.

Because both units measure volume per unit time, the conversion does not depend on the type of fluid. The same numerical relationship applies whether the flowing substance is air, water, oxygen, nitrogen, or another fluid, as long as the quantity being converted is volumetric flow rate.

When comparing equipment from different regions, ft3/min values are often found in North American product literature, while l/min values are more common in Europe, Asia, and many scientific settings. Accurate conversion helps avoid specification mismatches.

Quick Reference

Using the verified factor:

$$\text{l/min} = \text{ft3/min} \times 28.316831998815$$

Examples:

$$1 \ \text{ft3/min} = 28.316831998815 \ \text{l/min}$$

$$3 \ \text{ft3/min} = 84.950495996445 \ \text{l/min}$$

$$10 \ \text{ft3/min} = 283.16831998815 \ \text{l/min}$$

For reverse conversion:

$$\text{ft3/min} = \text{l/min} \times 0.03531468492103$$

This is helpful when a datasheet lists flow in litres per minute but a system requirement is expressed in cubic feet per minute.

Summary

Cubic feet per minute and litres per minute both measure volumetric flow rate, but they belong to different measurement systems. Using the verified relationship $1 \ \text{ft3/min} = 28.316831998815 \ \text{l/min}$ makes it straightforward to convert airflow or fluid flow values for technical, industrial, scientific, and commercial applications.

How to Convert Cubic feet per minute to Litres per minute

To convert Cubic feet per minute to Litres per minute, multiply the flow rate by the conversion factor between the two units. In this case, each $1$ ft$^3$/min equals $28.316831998815$ l/min.

1. Write down the given value:
   Start with the flow rate you want to convert:

   $$25\ \text{ft}^3/\text{min}$$

2. Use the conversion factor:
   The required conversion factor is:

   $$1\ \text{ft}^3/\text{min} = 28.316831998815\ \text{l/min}$$

3. Set up the multiplication:
   Multiply the given value by the conversion factor so the ft$^3$/min unit converts directly to l/min:

   $$25 \times 28.316831998815$$

4. Calculate the result:
   Perform the multiplication:

   $$25 \times 28.316831998815 = 707.92079997036$$

5. Result:

   $$25\ \text{ft}^3/\text{min} = 707.92079997036\ \text{l/min}$$

A quick way to check your work is to estimate: since $25 \times 28 \approx 700$, the final answer should be a little above $700$ l/min. This helps confirm the result is reasonable.

What is the formula to convert Cubic feet per minute to Litres per minute?

To convert Cubic feet per minute to Litres per minute, multiply the flow rate in $ft^3/min$ by the verified factor $28.316831998815$. The formula is $l/min = ft^3/min \times 28.316831998815$. This gives the equivalent volumetric flow rate in metric units.

How many Litres per minute are in 1 Cubic foot per minute?

There are exactly $28.316831998815\ l/min$ in $1\ ft^3/min$. This is the verified conversion factor used for all calculations on the page. It provides a direct way to switch from imperial to metric flow units.

Why would I convert Cubic feet per minute to Litres per minute?

This conversion is useful when comparing airflow or fluid flow specifications across systems that use different unit standards. For example, HVAC equipment, compressors, pumps, and ventilation systems may list flow in either $ft^3/min$ or $l/min$. Converting helps ensure accurate sizing, selection, and performance comparison.

Is Cubic feet per minute the same as Litres per minute?

No, they measure the same type of quantity—volumetric flow rate—but they are not the same unit. Cubic feet per minute is an imperial unit, while Litres per minute is a metric unit. You convert between them using $1\ ft^3/min = 28.316831998815\ l/min$.

Can I use the same conversion factor for air, water, and other fluids?

Yes, because this is a unit conversion for volume flow rate, not a property of a specific substance. The factor $1\ ft^3/min = 28.316831998815\ l/min$ applies regardless of whether the flowing medium is air, water, or another fluid. However, pressure, temperature, and density may still matter in engineering applications.

How do I convert a larger value from Cubic feet per minute to Litres per minute?

Multiply the number of $ft^3/min$ by $28.316831998815$ to get $l/min$. For example, the setup for $10\ ft^3/min$ is $10 \times 28.316831998815$. This method works for any flow value.