Convert pound per square inch to bar
1 pound per square inch = 0.06894757 bars
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.
What is bar?
A bar is a pressure unit approximately equal to standard atmospheric pressure, or 100,000 pascals. It is widely used in meteorology, hydraulics, diving equipment, and industrial pressure gauges.
Real-world uses
Bars are widely used in European tyre pressure specifications, compressed gas cylinder ratings, scuba diving depth gauges, and industrial process controls. Espresso machines operate at 9–15 bar. Atmospheric pressure is approximately 1.013 bar.
History
The bar was introduced by Norwegian meteorologist Vilhelm Bjerknes in 1909, derived from the Greek word "baros" meaning weight. Though not an SI unit, it is widely accepted in industry and was retained in the EU Directive on units of measurement.
Common mistakes
Confusing bar with atm—they are close (1 atm ≈ 1.01325 bar) but not identical. Also, gauge pressure (barg) versus absolute pressure (bara) is often mixed up; gauge pressure reads zero at atmospheric pressure.
When is this conversion used?
Converting between pound per square inch and bar 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 pound per square inch = 0.06894757 bars
1 bar = 100,000 pascals
How to convert pound per square inch to bar
To convert pound per square inch to bar, multiply the value by 0.06894757.
To convert bar back to pound per square inch, multiply by 14.50377377.
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 | bars |
|---|---|
| 0.1 | 0.00689476 |
| 0.5 | 0.03447379 |
| 1 | 0.06894757 |
| 2 | 0.13789515 |
| 5 | 0.34473786 |
| 10 | 0.68947573 |
| 25 | 1.72368932 |
| 50 | 3.44737865 |
| 100 | 6.89475729 |
| 250 | 17.23689323 |
| 500 | 34.47378647 |
| 1,000 | 68.94757293 |
Common values
| pounds per square inch | bars | |
|---|---|---|
| Car tyre | 31.9083023 pounds per square inch | 2.2 bars |
| Standard atmosphere | 14.69594878 pounds per square inch | 1.01325 bars |
| Blood pressure (systolic) | 2.3206038 pounds per square inch | 0.16 bars |
| Deep-sea submersible | 15,954.15115032 pounds per square inch | 1,100 bars |
| Bicycle tyre | 89.92339739 pounds per square inch | 6.2 bars |
Frequently asked questions
How many bars are in 1 pound per square inch?
1 pound per square inch = 0.06894757 bars.
How do you convert pound per square inch to bar?
Multiply the pound per square inch value by 0.06894757 to get bar.
What is 10 pounds per square inch in bars?
10 pounds per square inch = 0.68947573 bars.
How many pounds per square inch are in 1 bar?
1 bar = 14.50377377 pounds per square inch.
Available Pressure units
More pound per square inch conversions
- Convert pound per square inch to pascal
- Convert pound per square inch to kilopascal
- Convert pound per square inch to bar
- Convert pound per square inch to atmosphere
- Convert pound per square inch to millibar
- Convert pound per square inch to hectopascal
- Convert pound per square inch to torr
- Convert pound per square inch to inch of mercury
- Convert pound per square inch to megapascal