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Single conversion
To convert from bar (bar) to pound per square inch (psi), use the following formula:
With is the ratio between the base units kilopound per square inch (ksi) and kilopascal (kPa).
Let's convert 5 bar (bar) to pound per square inch (psi).
Using the formula:
Therefore, 5 bar (bar) is equal to pound per square inch (psi).
Here are some quick reference conversions from bar (bar) to pound per square inch (psi):
| bar | pounds per square inch |
|---|---|
| 0.000001 bar | psi |
| 0.001 bar | psi |
| 0.1 bar | psi |
| 1 bar | psi |
| 2 bar | psi |
| 3 bar | psi |
| 4 bar | psi |
| 5 bar | psi |
| 6 bar | psi |
| 7 bar | psi |
| 8 bar | psi |
| 9 bar | psi |
| 10 bar | psi |
| 20 bar | psi |
| 30 bar | psi |
| 40 bar | psi |
| 50 bar | psi |
| 100 bar | psi |
| 1000 bar | psi |
| 10000 bar | psi |
For all Pressure converters, choose units using the From/To dropdowns above.
The bar is a metric unit of pressure.
It is defined as exactly 100 kilopascals (kPa), or 100,000 Pascals (Pa).
Although it is not an official part of the International System of Units (SI), it is widely accepted for use with the SI. The bar is a popular unit for measuring pressure because it is very close to the average atmospheric pressure on Earth at sea level.
The term "bar" comes from the Greek word βάρος (baros), which means "weight."
The unit was introduced by British meteorologist William Napier Shaw in 1909. It is still widely used in meteorology, oceanography, and engineering.
A common point of confusion is the difference between a bar and a standard atmosphere (atm).
While they are very close in value, they are not the same:
This means 1 bar is approximately equal to 0.987 atm. Because it's so close to atmospheric pressure and is a round number (100 kPa), the bar is a very convenient unit for many applications.
The bar is a versatile unit used to measure pressure in many industrial and everyday contexts.
Common examples include:
A pound per square inch (PSI) is a unit of pressure commonly used in the imperial system (which is standard in the United States).
It measures the amount of force applied over a single square inch of area.
PSI is a critical measurement for safety and performance in many common items, including:
Vehicle Tires: Proper tire pressure (PSI) ensures optimal handling, fuel efficiency, and tire life. You can find the recommended level on a sticker inside the driver's door.
Home Water Pressure: Affects everything from shower performance to how well appliances like dishwashers and washing machines function.
Sports Equipment: Items like footballs, basketballs, and soccer balls require a specific PSI to perform correctly and safely.
Tools: Air compressors, pressure washers, and paint sprayers all have specific PSI ratings for safe and effective operation.
While PSI is standard in the imperial system, scientific and international contexts use metric (SI) units like the Pascal (Pa) and the bar.
PSI to Pascal (Pa): The official SI unit for pressure.
1 PSI ≈ 6,894.76 Pascals (or 6.895 kilopascals, kPa).
PSI to Bar: A common unit in automotive and weather contexts. 1 bar is roughly equal to atmospheric pressure at sea level.
1 PSI ≈ 0.0689 bar.
The term "PSI" can be specified further to give more context:
PSIG (Pound-force per square inch gauge): Measures pressure relative to the surrounding atmospheric pressure. This is the most common measurement, used by a standard tire gauge.
PSIA (Pound-force per square inch absolute): Measures pressure relative to a perfect vacuum (absolute zero pressure).
The formula is: PSIA = PSIG + local atmospheric pressure.
PSID (Pound-force per square inch differential): Measures the difference in pressure between two separate points in a system, such as across a filter or valve.