Convert CFM per Square Foot to cm³/(s·cm²)

Formula

cm³/(s·cm²) = ft³/(ft²·min) × 0.508

or cm³/(s·cm²) = ft³/(ft²·min) ÷ 1.968503937008

Derivation from SI units:

• 1 ft³/(ft²·min) = 0.3048³ m³ ÷ (0.3048² m² × 60 s) = 0.00508 m/s = 1 ft/min
• 1 cm³/(s·cm²) = 10⁻⁶ m³ ÷ (10⁻⁴ m² × 1 s) = 0.01 m/s = 1 cm/s
• 1 ft³/(ft²·min) = 0.00508 m/s ÷ 0.01 m/s per cm³/(s·cm²) = 0.508 cm³/(s·cm²)

Both units are defined exactly, so the factor is exact. CFM per Square Foot definition: cubic foot per square foot per minute; Cubic Centimeter per Second per Square Centimeter definition: cubic centimeter per second per square centimeter.

Worked examples

1. A needle felt at 50 ft³/(ft²·min) is 25.4 cm³/(s·cm²).
   50 ft³/(ft²·min) × 0.508 = 25.4 cm³/(s·cm²)
2. 1 ft³/(ft²·min) is 0.508 cm³/(s·cm²).
   1 ft³/(ft²·min) × 0.508 = 0.508 cm³/(s·cm²)

Where it's used

ASTM D737 allows reporting in either unit, so converting lets you compare SI and inch-pound reports from the same method.

CFM per Square Foot to other face velocity & air permeability units

Frequently asked questions

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".
• ASTM D737 Standard Test Method for Air Permeability of Textile Fabrics, ASTM International , SI results in cm³/s/cm².

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.