Gallon (US) per Minute to Cubic Foot per Minute (GPM to CFM)
Convert GPM to CFM — Flow Rate converter
One gallon (US) per minute equals 0.13368056 CFM, so to convert gallons (US) per minute to cubic feet per minute you multiply the value by 0.13368056. A gallon (US) per minute is smaller than a cubic foot per minute — going the other way, 1 CFM = 7.480519 GPM. For example, 10 GPM = 1.336806 CFM and 50 GPM = 6.684028 CFM.
1 GPM = 0.13368056 CFM
Gallon (US) per Minute to Cubic Foot per Minute formula
1 Gallon (US) per Minute = 0.13368056 CFM
Worked examples
- 25 GPM = 3.342014 CFM
- 100 GPM = 13.368056 CFM
Gallon (US) per Minute to Cubic Foot per Minute conversion table
| Gallon (US) per Minute (GPM) | Cubic Foot per Minute (CFM) |
|---|---|
| 1 | 0.13368056 |
| 2 | 0.26736111 |
| 3 | 0.40104167 |
| 5 | 0.66840278 |
| 8 | 1.069444 |
| 10 | 1.336806 |
| 12 | 1.604167 |
| 15 | 2.005208 |
| 20 | 2.673611 |
| 25 | 3.342014 |
| 50 | 6.684028 |
| 100 | 13.368056 |
| 250 | 33.420139 |
| 500 | 66.840278 |
| 1000 | 133.680556 |
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 GPM = 0.13368056 CFM.
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 minute are in one gallon (US) per minute?
One gallon (US) per minute equals 0.13368056 cubic feet per minute (CFM).
How many gallons (US) per minute are in one cubic foot per minute?
One cubic foot per minute equals 7.480519 gallons (US) per minute (GPM).
How do you convert gallons (US) per minute to cubic feet per minute?
1 Gallon (US) per Minute = 0.13368056 CFM. Use the calculator above for any value.
What is 5 GPM in CFM?
5 GPM = 0.66840278 CFM.
What is 100 GPM in CFM?
100 GPM = 13.368056 CFM.
What is 10 GPM in CFM?
10 GPM = 1.336806 CFM.
What is 20 GPM in CFM?
20 GPM = 2.673611 CFM.
What is 50 GPM in CFM?
50 GPM = 6.684028 CFM.
What is 500 GPM in CFM?
500 GPM = 66.840278 CFM.
Is a gallon (US) per minute bigger than a cubic foot per minute?
No. A gallon (US) per minute is smaller — one gallon (US) per minute equals 0.13368056 cubic feet per minute, while one cubic foot per minute equals 7.480519 gallons (US) per minute.