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    Pressure Units Explained: PSI, Bar, and Pascals

    UnitConvertLab Team
    2026-03-28
    5 min read

    What is Pressure?

    Pressure is simply force divided by the area it's applied to. In physics, the standard unit is the Pascal (Pa), but in daily life, we use everything from PSI to Bar.

    Common Pressure Units

    • PSI (Pounds per Square Inch): Used in the US for tires and scuba tanks.
    • Bar: Used in Europe for tires and weather. 1 Bar is roughly atmospheric pressure at sea level.
    • Pascal (Pa): The scientific standard. Usually seen as kiloPascals (kPa).
    • mmHg (Millimeters of Mercury): Used primarily in medicine for blood pressure.

    Handy Conversions

    • 1 Bar = 14.5038 PSI
    • 1 Bar = 100,000 Pascals
    • 1 PSI = 6.89476 kPa

    Key Takeaways

    • 30 PSI is about 2.1 Bar (standard car tire)
    • Atmospheric pressure is about 1 Bar or 101.3 kPa
    • High altitude lowers atmospheric pressure

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