pound per square inch (psi)
1 pound per square inch = 6,894.75729317 pascals
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.
Notes: Imperial/USCS unit
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 pound per square inch and pascal 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.
How to convert pound per square inch to pascal
To convert pound per square inch to pascal, multiply the value by 6,894.75729317.
Conversion formula (from base unit)
x * 6894.757293168
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.
| pounds per square inch | pascals |
|---|---|
| 0.1 | 689.47572932 |
| 0.5 | 3,447.37864658 |
| 1 | 6,894.75729317 |
| 2 | 13,789.51458634 |
| 5 | 34,473.78646584 |
| 10 | 68,947.57293168 |
| 25 | 172,368.9323292 |
| 50 | 344,737.8646584 |
| 100 | 689,475.7293168 |
| 250 | 1,723,689.323292 |
| 500 | 3,447,378.646584 |
| 1,000 | 6,894,757.293168 |
Common values
| pounds per square inch | pascals | |
|---|---|---|
| Car tyre | 31.9083023 pounds per square inch | 220,000 pascals |
| Standard atmosphere | 14.69594878 pounds per square inch | 101,325 pascals |
| Blood pressure (systolic) | 2.3206038 pounds per square inch | 16,000 pascals |
| Deep-sea submersible | 15,954.15115032 pounds per square inch | 110,000,000 pascals |
| Bicycle tyre | 89.92339739 pounds per square inch | 620,000 pascals |
Full pound per square inch conversion table
| Unit | Value | Factor |
|---|---|---|
| pascal | 1 psi = 6,894.75729317 Pa | × 6,894.75729317 |
| kilopascal | 1 psi = 6.89475729 kPa | × 6.89475729 |
| bar | 1 psi = 0.06894757 bar | × 0.06894757 |
| atmosphere | 1 psi = 0.06804596 atm | × 0.06804596 |
| millibar | 1 psi = 68.94757293 mbar | × 68.94757293 |
| hectopascal | 1 psi = 68.94757293 hPa | × 68.94757293 |
| torr | 1 psi = 51.71493257 Torr | × 51.71493257 |
| inch of mercury | 1 psi = 2.03602046 inHg | × 2.03602046 |
| megapascal | 1 psi = 0.00689476 MPa | × 0.00689476 |