m3/h to CFM Converter
Fan makers outside the US write m³/h. To get CFM, multiply by 0.5886.
Quick answer: multiply the flow in m³/h by 0.5886. For example, 10 m³/h is 5.886 CFM, 100 m³/h is 58.858 CFM and 500 m³/h is 294.29 CFM.
The m³/h to CFM formula
One m³ is 35.3147 cubic feet, and one hour is 60 minutes (Wikipedia: Cubic foot).
So CFM equals m³/h times 35.3147, divided by 60, which is 0.5886.
Take 10 m³/h. Multiply by 0.5886. The answer is 5.886 CFM.
Take 100 m³/h. Multiply by 0.5886. The answer is 58.858 CFM.
Metres per hour to feet per minute
Noctua gives 1 m³/h as about 0.589 CFM (Noctua FAQ).
Its table lists 100 m³/h as 58.86 CFM (Noctua FAQ).
The factor joins a cubic metre to a cubic foot and an hour to a minute.
How to convert m³/h to CFM step by step
- Write down the flow in m³/h.
- Multiply it by 0.5886.
- The answer is in CFM.
- Check it against the chart above.
Example 1: 10 m³/h
- Start with 10 m³/h.
- 10 × 0.5886 = 5.886.
- The flow is 5.886 CFM.
10 m³/h = 5.886 CFM
Example 2: 100 m³/h
- Start with 100 m³/h.
- 100 × 0.5886 = 58.858.
- The flow is 58.858 CFM.
100 m³/h = 58.858 CFM
Example 3: 500 m³/h
- Start with 500 m³/h.
- 500 × 0.5886 = 294.29.
- The flow is 294.29 CFM.
500 m³/h = 294.29 CFM
Noctua lists 100 m³/h as 58.86 CFM, which matches this factor (Noctua FAQ).
m³/h to CFM conversion table
| m³/h | CFM | L/s |
|---|---|---|
| 1 m³/h | 0.5886 CFM | 0.2778 L/s |
| 10 m³/h | 5.886 CFM | 2.778 L/s |
| 50 m³/h | 29.429 CFM | 13.889 L/s |
| 100 m³/h | 58.858 CFM | 27.778 L/s |
| 250 m³/h | 147.14 CFM | 69.444 L/s |
| 500 m³/h | 294.29 CFM | 138.89 L/s |
| 1,000 m³/h | 588.58 CFM | 277.78 L/s |
| 2,000 m³/h | 1,177.16 CFM | 555.56 L/s |
The highlighted row, 10 m³/h, is the default of the converter. The last column gives L/s.
A quick mental shortcut for m³/h to CFM
Multiply the m³/h by 0.6. So 100 m³/h is about 60 CFM.
For a closer answer, take off 2 percent.
What m³/h measures
The m³/h unit is cubic metres per hour. Many fan makers outside the US list it.
It is also written CMH.
What CFM measures
CFM means cubic feet per minute. It shows how much air passes a point each minute (Wikipedia: Cubic foot).
US fan sheets use it.
Where 0.5886 comes from
One cubic metre holds 35.3147 cubic feet. There are 60 minutes in an hour.
So 35.3147 ÷ 60 = 0.5886.
Actual and standard CFM
Air squeezes and expands, so CFM can mean actual or standard flow (Wikipedia: Actual cubic feet per minute).
This page only changes units.
Reading a PC fan
A PC fan listed at 100 m³/h gives 58.86 CFM (Noctua FAQ).
A fan of 150 m³/h gives 88.29 CFM.
Room ventilation
A fan of 300 m³/h gives 176.6 CFM.
That can serve a small room.
Going the other way
To go back, divide the CFM by 0.5886. Or multiply by 1.699.
So 58.86 CFM is 100 m³/h.
Hours to minutes
m³/h is per hour and CFM is per minute. That is why 60 sits in the factor.
Skip it and you are 60 times off.
Check your answer
Your CFM should be about 59 percent of the m³/h.
Divide it by 0.5886 and you should get your first number.
More values at a glance
1 m³/h is 0.58858 CFM, 5 m³/h is 2.9429 CFM and 10 m³/h is 5.8858 CFM.
50 m³/h is 29.429 CFM, 100 m³/h is 58.858 CFM and 500 m³/h is 294.29 CFM.
1,000 m³/h is 588.58 CFM, and 5,000 m³/h is 2,942.9 CFM.
The unit sizes
One m³ is about 35.31 cubic feet, and an hour is 60 minutes. So 1 m³/h is about 0.5886 CFM.
If a result looks very large or very small, compare it with these sizes before you use it.
Checking in reverse
Convert 5.8858 CFM back to m³/h. You should get 10 m³/h.
Quick conversion answers
| Conversion | Result |
|---|---|
| 10 m³/h | 5.886 CFM |
| 50 m³/h | 29.429 CFM |
| 100 m³/h | 58.858 CFM |
| 250 m³/h | 147.14 CFM |
| 500 m³/h | 294.29 CFM |
| 1,000 m³/h | 588.58 CFM |
Round numbers for m³/h and CFM
Use these round numbers to check your own answer. 50 m³/h is 29.43 CFM, 500 m³/h is 294.3 CFM and 5,000 m³/h is 2,943 CFM.
Going the other way, 5 CFM is 8.495 m³/h, 50 CFM is 84.95 m³/h and 500 CFM is 849.5 m³/h.
A round trip with m³/h
Say you start with 370 m³/h. It becomes 217.8 CFM. Divide that by the factor and you land on 370 m³/h again.
Now start from 250 CFM instead. It becomes 424.7 m³/h, and multiplying by the factor returns 250 CFM.
Where this conversion is used
Pumps and fans are rated in cubic meters per hour.
Fans and air systems are rated in cubic feet per minute.
Buyers compare PC and room fans.
HVAC staff check vent flow.
Common mistakes to avoid
- Mixing up minutes and hours. CFM is per minute. m³/h is per hour.
- Using the wrong direction. Here 10 m³/h is 5.886 CFM, so a correct answer comes out smaller than the number you start with.
- Mixing actual and standard flow. The unit change does not fix the air condition.
- Rounding too early. The answer for 250 m³/h is 147.14 CFM. Cut it to 150 CFM and you are off by about 1.9 percent, and the gap grows if you reuse it.
Related converters
A bathroom fan
A fan of 120 m³/h is 70.63 CFM.
That is a common size.
A kitchen hood
A hood of 800 m³/h is 470.9 CFM.
Check it against the room size.
A workshop fan
A fan of 2,000 m³/h is 1,177 CFM.
It moves a large volume.
Frequently asked questions
How do I convert m³/h to CFM?
Multiply the m³/h by 0.5886.
How many CFM is 100 m³/h?
About 58.86 CFM.
How many m³/h is 1 CFM?
About 1.699 m³/h.
Is m³/h the same as CMH?
Yes.
Why is there a 60?
m³/h is per hour and CFM is per minute.
Does air temperature matter?
Not for the unit change.
Sources
- Wikipedia: Cubic foot (en.wikipedia.org)
- Wikipedia: Actual cubic feet per minute (en.wikipedia.org)
- Noctua FAQ: You specify airflow in m³/h, how can I convert it to CFM? (noctua.at)
