Cubic Foot per Minute to Cubic Foot per Second (CFM to CFS)
Convert CFM to CFS — Flow Rate converter
One cubic foot per minute equals 0.01666667 CFS, so to convert cubic feet per minute to cubic feet per second you multiply the value by 0.01666667. A cubic foot per minute is smaller than a cubic foot per second — going the other way, 1 CFS = 60 CFM. For example, 10 CFM = 0.16666667 CFS and 50 CFM = 0.83333333 CFS.
1 CFM = 0.01666667 CFS
Cubic Foot per Minute to Cubic Foot per Second formula
1 Cubic Foot per Minute = 0.01666667 CFS
Worked examples
- 25 CFM = 0.41666667 CFS
- 100 CFM = 1.666667 CFS
Cubic Foot per Minute to Cubic Foot per Second conversion table
| Cubic Foot per Minute (CFM) | Cubic Foot per Second (CFS) |
|---|---|
| 1 | 0.01666667 |
| 2 | 0.03333333 |
| 3 | 0.05 |
| 5 | 0.08333333 |
| 8 | 0.13333333 |
| 10 | 0.16666667 |
| 12 | 0.2 |
| 15 | 0.25 |
| 20 | 0.33333333 |
| 25 | 0.41666667 |
| 50 | 0.83333333 |
| 100 | 1.666667 |
| 250 | 4.166667 |
| 500 | 8.333333 |
| 1000 | 16.666667 |
Which gallon, and which trade
The single most expensive mistake in flow conversion is the gallon. A US liquid gallon is 3.785411784 litres; an imperial gallon is 4.54609 litres. US GPM and imperial GPM differ by about 20%, and pump datasheets frequently do not say which one they mean. Check the manufacturer's country of origin before trusting a GPM figure.
Different trades default to different units for the same physical quantity: HVAC and compressed air work in CFM, plumbing and pumps in GPM or LPM, and process and water engineering in m³/h or L/s. A specification that mixes them is usually quoting different equipment, not different flows. On this page, 1 CFM = 0.01666667 CFS.
CFM to metric is worth memorising: one cubic foot is exactly 0.028316846592 m³, so 1 CFM = 1.699011 m³/h and 1,000 CFM ≈ 1,699 m³/h. Note that CFM on a compressor may be quoted as free air delivery (FAD) at inlet conditions rather than at working pressure — the two are not interchangeable.
Frequently asked questions
How many cubic feet per second are in one cubic foot per minute?
One cubic foot per minute equals 0.01666667 cubic feet per second (CFS).
How many cubic feet per minute are in one cubic foot per second?
One cubic foot per second equals 60 cubic feet per minute (CFM).
How do you convert cubic feet per minute to cubic feet per second?
1 Cubic Foot per Minute = 0.01666667 CFS. Use the calculator above for any value.
What is 5 CFM in CFS?
5 CFM = 0.08333333 CFS.
What is 100 CFM in CFS?
100 CFM = 1.666667 CFS.
What is 10 CFM in CFS?
10 CFM = 0.16666667 CFS.
What is 20 CFM in CFS?
20 CFM = 0.33333333 CFS.
What is 50 CFM in CFS?
50 CFM = 0.83333333 CFS.
What is 500 CFM in CFS?
500 CFM = 8.333333 CFS.
Is a cubic foot per minute bigger than a cubic foot per second?
No. A cubic foot per minute is smaller — one cubic foot per minute equals 0.01666667 cubic feet per second, while one cubic foot per second equals 60 cubic feet per minute.