What is kilopascal?
A kilopascal is a metric pressure unit equal to 1,000 pascals. It is used for weather forecasts, tire pressure specifications in metric countries, and structural and mechanical engineering calculations.
Real-world uses
Kilopascals are used for tyre pressure in most countries (standard car tyres are about 200–250 kPa), blood pressure in some medical systems, and hydraulic system specifications. Atmospheric pressure at sea level is approximately 101.325 kPa.
History
The kilopascal became a practical engineering unit with the adoption of the SI system. It offers a convenient scale for everyday pressure measurements, bridging the gap between the tiny pascal and the larger bar or atmosphere.
Common mistakes
Confusing kPa with psi when checking tyre pressure. 1 psi ≈ 6.895 kPa, so 32 psi ≈ 220 kPa. Inflating a tyre to 32 kPa instead of 220 kPa would leave it nearly flat.
What is pound per square inch?
Pound per square inch (psi) is an imperial pressure unit widely used in the United States for tire inflation, hydraulic system pressures, gas cylinder ratings, and plumbing specifications.
Real-world uses
PSI is the standard pressure unit in the United States for tyre inflation (typically 30–35 psi for cars), compressed air tools, hydraulic systems, and water pressure. HVAC systems, fire extinguisher ratings, and pressure cooker specifications use psi in North America.
History
Pounds per square inch emerged naturally from the Imperial/US customary system, combining the pound-force with the square inch. It became the dominant pressure unit in American industry and remains deeply embedded in US engineering standards and building codes.
Common mistakes
Not distinguishing between psi (absolute, psia) and psig (gauge, relative to atmosphere). A tyre reading of 32 psig actually means about 46.7 psia. Also, confusing psi with kPa when using equipment from metric countries.
When is this conversion used?
Converting between kilopascal and pound per square inch is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region. Tyre pressure gauges, HVAC systems, and industrial equipment may use different pressure units depending on the manufacturer and region. Converting between psi, bar, and kPa is common in automotive and engineering work.
Worked examples
1 kilopascal = 0.14503774 pound per square inch
1 pound per square inch = 6,894.75729317 pascal
How to convert kilopascal to pound per square inch
To convert kilopascal to pound per square inch, multiply the value by 0.14503774.
To convert pound per square inch back to kilopascal, multiply by 6.89475729.
Measurement standards
The pascal (Pa) is the SI derived unit of pressure, defined as one newton per square metre. The World Meteorological Organization mandates the hectopascal (hPa) for atmospheric pressure reporting in aviation and weather services.
Did you know?
The pressure at the bottom of the Mariana Trench, nearly 11 km deep, exceeds 1,086 bar — over a thousand times atmospheric pressure. At this depth, water is compressed by about 5%, making it measurably denser than at the surface.
Quick reference: kilopascal to pound per square inch
| kilopascal | pound per square inch |
|---|---|
| 0.1 | 0.01450377 |
| 0.5 | 0.07251887 |
| 1 | 0.14503774 |
| 2 | 0.29007548 |
| 5 | 0.72518869 |
| 10 | 1.45037738 |
| 25 | 3.62594344 |
| 50 | 7.25188689 |
| 100 | 14.50377377 |
| 250 | 36.25943443 |
| 500 | 72.51886887 |
| 1,000 | 145.03773773 |
Common values
| kilopascal | pound per square inch | |
|---|---|---|
| Car tyre | 220 kilopascal | 31.9083023 pound per square inch |
| Standard atmosphere | 101.325 kilopascal | 14.69594878 pound per square inch |
| Blood pressure (systolic) | 16 kilopascal | 2.3206038 pound per square inch |
| Deep-sea submersible | 110,000 kilopascal | 15,954.15115032 pound per square inch |
| Bicycle tyre | 620 kilopascal | 89.92339739 pound per square inch |