Why does PSI use 'pounds'? Aren't those weight units?

PSI uses pound-force (lbf), a unit of force, not the pound of mass. 1 lbf is the weight of a 1 lb mass under standard gravity.

Is PSI or kPa bigger numerically?

kPa is numerically larger. 1 psi ≈ 6.9 kPa. The conversion multiplies by ~7.

PSI to Kilopascals (kPa) Converter

Enter a value to instantly convert between pressure units.

From

Precision4 dp

1 Pound per Sq. Inch = 6.8948 Kilopascal

Key Formulas

Pound per Sq. Inch → Bar

bar = psi × 0.0689476

Bar → Pound per Sq. Inch

psi = bar × 14.5038

Atmosphere → Pound per Sq. Inch

psi = atm × 14.6959

Pound per Sq. Inch → Atmosphere

atm = psi × 0.068046

Formula

kPa = psi × 6.89476

PSI (pounds per square inch) is the US imperial pressure unit; kilopascals (kPa) are metric SI. The conversion factor 6.89476 comes from 1 lbf = 4.44822 N acting on 1 in² = 0.00064516 m². Essential for translating US equipment specs to international standards.

Source: NIST SP 811, Table B.8

Reviewed by the Convert Calc editorial team · Last reviewed: 2026-10-06 · see our methodology

Frequently Asked Questions

Real-World Examples

Close to sea-level air pressure. 14.5 psi ≈ 100 kPa, or about 1 bar.

14.5 psi = 100 kPa

Tire pressure example. 30 psi ≈ 207 kPa.

30 psi = 207 kPa

Household water pressure example. 60 psi ≈ 414 kPa.

60 psi = 414 kPa

Atmospheric pressure. 14.696 psi = 101.325 kPa. Sea level standard.

14.696 psi = 101.325 kPa

psi to bar bar to psi atm to psi psi to atm kpa to psi

See This in Context

Weather HVAC Tire Pressure Conversion Chart: PSI to Bar and kPa