Pounds Per Square Foot to Kilopascals (psf to kPa)

1 pound per square foot equals 0.04788025898 kilopascals (rounded).

1 pound per square foot = 0.04788025898 kilopascals

How to convert pounds per square foot to kilopascals

To convert pounds per square foot to kilopascals, multiply the number of pounds per square foot by 0.04788025898. The factor is rounded to 10 significant digits. To go the other way, multiply kilopascals by 20.88543423 (rounded).

kilopascals = pounds per square foot × 0.04788025898

Example: 10 pounds per square foot = 0.4788025898 kilopascals.

About these units

Pound Per Square Foot (psf)

US & ImperialTraditional unit (still used in some regions)

About 47.88 pascals. Used in US structural engineering for distributed loads.

A square foot is 144 square inches, so one pound per square foot is one 144th of a psi, which comes to about 47.88 Pa; NIST gives 47.88026. The number is easy to picture: spread one pound-force evenly over a floor tile a foot across and that is the pressure, tiny compared with the 101,325 Pa of one standard atmosphere.

Building codes in the United States commonly state loads on floors and roofs this way, and snow and wind pressures are tabulated in the same unit. Metric countries use kilopascals or newtons per square metre instead, and 1 kPa is about 20.9 psf. Multiplying a psf figure by 144 gives psi, and by 47.88 gives pascals, so a 40 psf floor load is about 1.9 kPa.

1 pound per square foot = 47.88025898 pascals (approximately).

Sources: NIST SP 811, Appendix B.8; Wikipedia: Pounds per square inch

Kilopascal (kPa)

Metric (SI)Current unit

1,000 pascals. Used for tire pressures, weather reports in many countries and engineering.

Kilopascal is the form of the pascal that most people actually use. The pascal itself is very small, so outside meteorology the kilopascal became the common choice in most fields, and it equals one centibar. Medical elastography reports tissue stiffness in kPa, and Canada reports atmospheric pressure in kPa rather than hectopascals.

A standard atmosphere is 101.325 kPa. In 1982 IUPAC recommended a different reference for chemistry, a standard pressure of exactly 100 kPa, which split the older convention of 1 atm into two competing standards.

Blood pressure shows how the units line up. One mmHg is 0.13332 kPa, and a normal reading is below about 16.0 kPa systolic and 10.7 kPa diastolic, the same thing as the familiar 120 over 80 in millimeters of mercury.

1 kilopascal = 1,000 pascals (exactly).

Sources: Wikipedia: Pascal (unit); Wikipedia: Standard atmosphere (unit); Wikipedia: Millimetre of mercury

Related conversions

See all pressure units.