Bar (bar) - Unit Information & Conversion
🔄 Quick Convert Bar
What is a Bar?
Bar is a metric unit of pressure equal to 100,000 pascals, approximately equal to atmospheric pressure at sea level. Widely used in Europe for tire pressure, hydraulics, meteorology, and industrial applications.
History of the Bar
Introduced in 1909 by British meteorologist William Napier Shaw. The name comes from "barometer". Officially recognized in the International System of Units (SI) as a non-SI unit accepted for use with SI, due to its widespread use in various fields.
Quick Answer
What is a bar? A bar is a unit of pressure equal to 100,000 pascals (Pa) or 100 kilopascals (kPa). It's approximately equal to atmospheric pressure at sea level (1.013 bar). Widely used in Europe for tire pressure (typically 2-2.5 bar for cars), hydraulics, and weather reporting. Use our pressure converter to convert bar to PSI, kPa, and other units instantly.
Quick Comparison Table
| Bar | PSI | kPa | Context | Convert Now |
|---|---|---|---|---|
| 1 | 14.5 | 100 | Atmospheric pressure | Bar to PSI → |
| 2 | 29.0 | 200 | Bicycle tire (low) | Bar to kPa → |
| 2.2-2.4 | 32-35 | 220-240 | Car tire pressure | Bar to PSI → |
| 5-10 | 72-145 | 500-1,000 | Hydraulic systems | Bar to PSI → |
| 6-8 | 87-116 | 600-800 | Compressed air tools | Bar to kPa → |
Definition
The bar is a metric unit of pressure defined as exactly 100,000 pascals (100 kPa). One bar is approximately equal to atmospheric pressure at sea level. 1 bar = 100,000 Pa = 100 kPa = 14.5038 PSI = 0.986923 atm.
History
Introduced in 1909 by British meteorologist William Napier Shaw. Named after "barometer". Recognized by CIPM in 1982 as acceptable for use with SI units due to widespread adoption in industry and meteorology.
Common Uses
European Automotive: Universal tire pressure unit in Europe. Car tires typically 2.0-2.5 bar. Industrial: Standard for hydraulics, compressed air, and pneumatics. Meteorology: Used alongside millibar (mbar) for weather reporting. Diving: Scuba tank pressures (200-300 bar).
Bar Conversion Formulas
To Pascal:
To Kilopascal:
To Megapascal:
To Hectopascal:
To Millibar:
To Atmosphere:
To Technical Atmosphere:
To Torr:
To Millimeter of Mercury:
To Inch of Mercury:
To Pound per Square Inch:
To Kilopound per Square Inch:
To Kilogram-force per Square Centimeter:
To Kilogram-force per Square Meter:
To Millimeter of Water Column:
To Inch of Water Column:
Frequently Asked Questions
Convert Bar
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