Volumetric Flow Rate Converter – CFM to m³/h, L/s & m³/s in 3 Easy Steps
Volumetric Flow Converter
Use this volumetric flow rate converter: type a value into any unit field to instantly convert across all airflow and fluid flow measurements.
Use this free volumetric flow rate converter to switch between cubic feet per minute (CFM), cubic meters per hour (m³/h), liters per second (L/s) and cubic meters per second (m³/s). Type a value into any box and the other three update instantly, which makes CFM to m³/h conversions for fans, ducts and HVAC equipment quick and error-free.
Quick answer
1 CFM = 1.699 m³/h = 0.4719 L/s. To convert CFM to m³/h, multiply by 1.699. To convert m³/h to CFM, multiply by 0.5886 (or divide by 1.699). For example, 400 CFM = 679.6 m³/h = 188.8 L/s, and 500 m³/h = 294.3 CFM.
Table of Contents
Airflow figures come in different units depending on where the equipment was made. US fan and HVAC catalogues list CFM, while European and Asian datasheets use m³/h or L/s. Engineers, HVAC installers and anyone comparing a bathroom fan or air purifier often need to convert between them.
This volumetric flow rate converter does all four conversions at once and keeps a quick reference matrix on screen. It runs in your browser with no sign-up.
What Is Volumetric Flow Rate?
Volumetric flow rate is the volume of air, gas or liquid that passes a point in a given time. It is written as Q and equals the flow speed multiplied by the cross-section area: Q = v × A. A duct with air moving at 2 m/s through a 0.1 m² opening carries 0.2 m³/s, or 720 m³/h.
It is different from mass flow rate, which measures kilograms per second. For air at normal room conditions you can treat the two as proportional, but for hot gases or compressed air the density changes and the difference matters.
Volumetric Flow Rate Conversion Formulas
- CFM to m³/h: m³/h = CFM × 1.69901
- m³/h to CFM: CFM = m³/h × 0.58858
- CFM to L/s: L/s = CFM × 0.47195
- L/s to CFM: CFM = L/s × 2.11888
- L/s to m³/h: m³/h = L/s × 3.6
- m³/s to m³/h: m³/h = m³/s × 3,600
All of these come from one fact: 1 cubic foot = 0.0283168 m³, and there are 60 minutes in an hour, so 1 CFM = 0.0283168 × 60 = 1.699 m³/h.
CFM to m³/h Conversion Table
| CFM | m³/h | L/s |
|---|---|---|
| 50 | 85.0 | 23.6 |
| 100 | 169.9 | 47.2 |
| 200 | 339.8 | 94.4 |
| 400 | 679.6 | 188.8 |
| 1,000 | 1,699.0 | 471.9 |
| 2,000 | 3,398.0 | 943.9 |
m³/h to CFM Conversion Table
| m³/h | CFM | L/s |
|---|---|---|
| 100 | 58.9 | 27.8 |
| 250 | 147.1 | 69.4 |
| 500 | 294.3 | 138.9 |
| 1,000 | 588.6 | 277.8 |
| 3,000 | 1,765.7 | 833.3 |
How to Use the Volumetric Flow Rate Converter
Step 1: Type a Value in Any Unit
Click the box for the unit you already have and type your number. In this example, 400 CFM is entered, and the converter instantly shows 679.604318 m³/h, 188.778977 L/s and 0.188779 m³/s.
Step 2: Convert Back the Other Way
There is no need to switch direction. Type in the m³/h box instead and the CFM value updates. A fan rated at 500 m³/h moves 294.29 CFM, or 138.89 L/s.
Step 3: Use the Reference Matrix
The matrix under the fields lists the most-used factors: 1 CFM = 1.6990 m³/h, 1 m³/h = 0.5885 CFM, 1 CFM = 0.4719 L/s and 1 L/s = 3.6 m³/h. Use it for quick mental checks, and press Clear Fields to start again.
Common Airflow Values in CFM and m³/h
These typical figures help put a number in context. Always follow the manufacturer’s data and your local building code for real designs.
| Application | Typical airflow (CFM) | Approx. m³/h |
|---|---|---|
| Bathroom exhaust fan | 50 to 110 | 85 to 187 |
| Kitchen range hood (home) | 150 to 400 | 255 to 680 |
| Central air conditioning, per ton of cooling | about 400 | about 680 |
| Portable air purifier (room) | 100 to 300 | 170 to 510 |
| Small desk fan | up to about 1,000 | up to about 1,700 |
Tips for Accurate Airflow Conversions
- Check whether a datasheet lists free-air flow or flow at a stated static pressure. Real airflow in ducts is lower.
- Watch for SCFM (standard cubic feet per minute) in compressed-air specs. It refers to air at standard conditions, not the actual volume at pressure.
- Keep enough decimals while you work and round only the final answer.
- For liquids, US gallons per minute (GPM) are common: 1 US GPM ≈ 0.227 m³/h ≈ 0.134 CFM.
Working on other technical conversions? Try the Radiation Converter for dose units or the Length Converter for feet and meters.
Frequently Asked Questions
How do I convert CFM to m³/h?
Multiply the CFM value by 1.699. For example, 200 CFM × 1.699 = 339.8 m³/h.
How do I convert m³/h to CFM?
Multiply by 0.5886, or divide by 1.699. For example, 500 m³/h ≈ 294.3 CFM.
How many liters per second is 1 CFM?
1 CFM equals about 0.472 liters per second, and 1 L/s equals about 2.119 CFM.
What is the difference between CFM and SCFM?
CFM is the actual volume of air moved. SCFM is the volume corrected to standard temperature and pressure, used mainly for compressors and gas flow.
Can I use this converter for water and other liquids?
Yes. Volume units are the same for any fluid, so the converter works for water, oil or gas as long as you need volume per time.
How accurate is the volumetric flow rate converter?
It uses the exact definition of the cubic foot, 0.0283168 m³, and shows results to six decimal places.