Convert CFM per Square Foot to Millimeters per Second
1 cubic foot per square foot per minute (ft³/(ft²·min)) equals 5.08 millimeters per second (mm/s).
1 ft³/(ft²·min) = 5.08 mm/s
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk cubic foot per square foot per minute to millimeter per second converter to paste a column from Excel.
How to Convert CFM per Square Foot to Millimeter per Second
- 1 ft³/(ft²·min) = 5.08 mm/s
- 1 mm/s = 0.1968503937 ft³/(ft²·min)
- Example: convert 15 ft³/(ft²·min) to mm/s: 15 ft³/(ft²·min) = 15 × 5.08 mm/s = 76.2 mm/s
Formula
mm/s = ft³/(ft²·min) × 5.08
Derivation from SI units:
- 1 ft³/(ft²·min) = 0.3048³ m³ ÷ (0.3048² m² × 60 s) = 0.00508 m/s = 1 ft/min
- 1 mm/s = 0.001 m ÷ 1 s = 1 L/(m²·s)
- 1 ft³/(ft²·min) = 0.00508 m/s ÷ 0.001 m/s per mm/s = 5.08 mm/s
Both units are defined exactly, so the factor is exact. CFM per Square Foot definition: cubic foot per square foot per minute; Millimeter per Second definition: millimeter per second.
Worked examples
- A fabric at 30 ft³/(ft²·min) is 152.4 mm/s.
30 ft³/(ft²·min) × 5.08 = 152.4 mm/s - 1 ft³/(ft²·min) is exactly 5.08 mm/s.
1 ft³/(ft²·min) × 5.08 = 5.08 mm/s
CFM per Square Foot to Millimeter per Second conversion table
| CFM per Square Foot (ft³/(ft²·min)) | Millimeters per Second (mm/s) |
|---|---|
| 1 ft³/(ft²·min) | 5.08 mm/s |
| 2 ft³/(ft²·min) | 10.16 mm/s |
| 5 ft³/(ft²·min) | 25.4 mm/s |
| 10 ft³/(ft²·min) | 50.8 mm/s |
| 15 ft³/(ft²·min) | 76.2 mm/s |
| 20 ft³/(ft²·min) | 101.6 mm/s |
| 25 ft³/(ft²·min) | 127 mm/s |
| 30 ft³/(ft²·min) | 152.4 mm/s |
| 40 ft³/(ft²·min) | 203.2 mm/s |
| 50 ft³/(ft²·min) | 254 mm/s |
| 60 ft³/(ft²·min) | 304.8 mm/s |
| 75 ft³/(ft²·min) | 381 mm/s |
| 100 ft³/(ft²·min) | 508 mm/s |
| 150 ft³/(ft²·min) | 762 mm/s |
| 200 ft³/(ft²·min) | 1016 mm/s |
| 300 ft³/(ft²·min) | 1524 mm/s |
| 500 ft³/(ft²·min) | 2540 mm/s |
| 1000 ft³/(ft²·min) | 5080 mm/s |
Where it's used
US Frazier and ASTM D737 values in CFM/ft² are converted to mm/s to compare with ISO 9237 results.
CFM per Square Foot to other face velocity & air permeability units
Frequently asked questions
How many mm/s is 1 CFM/ft²?
Exactly 5.08 mm/s.
How many millimeters per second are in 1 cubic foot per square foot per minute?
1 ft³/(ft²·min) = 5.08 mm/s.
How do I convert cubic feet per square foot per minute to millimeters per second?
Multiply the value in ft³/(ft²·min) by 5.08. For example, 15 ft³/(ft²·min) × 5.08 = 76.2 mm/s.
Is the ft³/(ft²·min) to mm/s conversion exact?
Yes. Both units are defined exactly, and 1 ft³/(ft²·min) is exactly 5.08 mm/s.
Sources
- ASTM D737 Standard Test Method for Air Permeability of Textile Fabrics, ASTM International , inch-pound results in ft³/min/ft².
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "foot per minute".
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 2 with SI prefix milli.
- ISO 9237:1995 Textiles — Determination of the permeability of fabrics to air, International Organization for Standardization , results expressed in mm/s.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert CFM per Square Foot to Millimeters per Second. Retrieved October 17, 2026, from https://scientificconverters.com/face-velocity/cfm-per-square-foot-to-millimeters-per-second/
IEEE
Scientific Converters, "Convert CFM per Square Foot to Millimeters per Second," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/face-velocity/cfm-per-square-foot-to-millimeters-per-second/