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Convert psi to bar

Please provide values below to convert psi [psi] to bar, or vice versa.


Pound-force per square inch

Definition: A pound-force per square inch (symbol: psi) is an imperial and US customary unit of pressure based on avoirdupois units. It is defined as the pressure that results when a force of one pound-force is applied to a one-square-inch area. One psi is approximately 6,895 pascals (N/m2).

History/origin: Pound-force per square inch is a unit that originated in the imperial and US customary systems of units. It is based on the avoirdupois system, a system that uses weights in terms of the avoirdupois pound, which was standardized in 1959. The system is believed to have come into use in England around 1300 and was used in the international wool trade. As such, the prototype pound at the time was known as the avoirdupois wool pound.

Current use: The psi is fairly widely used to measure numerous pressures, such as tire pressure, scuba tank pressure, natural gas pipeline pressure, among others. Although the pascal is more widely used in scientific contexts, psi is more often used in everyday contexts, particularly in countries like the United States as well as others under the US customary or imperial systems of units.


Definition: A bar (symbol: bar) is a metric unit of pressure that is defined as exactly 100,000 pascals (symbol: Pa). It is equal to 0.987 atmospheres (101,325 Pa), the unit often used as a reference of standard pressure.

History/origin: The unit, bar, was introduced by Vilhelm Bjerknes, a Norwegian meteorologist who founded modern weather forecasting. The term "bar" comes from the Greek word "baros," which means weight.

Current use: Although the bar is a metric unit of pressure, it is not accepted within the International System of Units (SI) and is even deprecated within certain fields. The International Bureau of Weights and Measures has specified the bar as a unit that authors should have the freedom to use but has chosen not to include the bar in the list of non-SI units accepted for use with SI.

Millibars (symbol: mb) are also commonly used when referencing atmospheric air pressure, where atmospheric pressure equals 1013.25 mbar (101.325 kPa). Meteorologists and weather reporters worldwide often use this unit for convenience, since working in pascals would result in much larger values.

Psi to Bar Conversion Table

Psi [psi]Bar
0.01 psi0.0006894757 bar
0.1 psi0.0068947573 bar
1 psi0.0689475729 bar
2 psi0.1378951459 bar
3 psi0.2068427188 bar
5 psi0.3447378647 bar
10 psi0.6894757293 bar
20 psi1.3789514586 bar
50 psi3.4473786466 bar
100 psi6.8947572932 bar
1000 psi68.9475729318 bar

How to Convert Psi to Bar

1 psi = 0.0689475729 bar
1 bar = 14.503773773 psi

Example: convert 15 psi to bar:
15 psi = 15 × 0.0689475729 bar = 1.034213594 bar

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