Pressure Unit Converter

Convert between different barometric pressure units instantly

Pressure Unit Converter

Convert between different pressure units by selecting the units and entering a value

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converts to

Understanding Pressure Units

Common Weather Units

  • inHg (Inches of Mercury): Used primarily in the United States for weather reports and aviation
  • mb/hPa (Millibars/Hectopascals): International standard for meteorology (they are equivalent)
  • mmHg (Millimeters of Mercury): Common in medicine and some countries

Scientific Units

  • Pa (Pascals): The SI base unit of pressure
  • kPa (Kilopascals): 1,000 Pascals, commonly used in engineering
  • atm (Atmospheres): Based on average sea-level pressure

Reference Values

Standard Sea Level Pressure:

  • 29.92 inHg
  • 1013.25 mb/hPa
  • 760 mmHg
  • 14.696 psi
  • 1 atm
  • 101,325 Pa

Pressure Categories

  • High Pressure: Above 30.20 inHg (1022 mb)
  • Normal Pressure: 29.80-30.20 inHg (1009-1022 mb)
  • Low Pressure: Below 29.80 inHg (1009 mb)
  • Hurricane Low: Can drop below 28.00 inHg (948 mb)

Quick Conversion Tables

Common Weather Pressures

Condition inHg mb mmHg
Hurricane Low 27.00 914 686
Very Low 28.50 965 724
Low Pressure 29.50 999 749
Normal 29.92 1013 760
High Pressure 30.50 1033 775
Very High 31.00 1050 787

Unit Conversion Chart

From To Multiply by
inHg mb 33.864
mb inHg 0.02953
inHg mmHg 25.4
mb hPa 1.0
kPa mb 10.0
psi mb 68.948
atm mb 1013.25
Pa mb 0.01

Altitude vs Pressure

Altitude Pressure (inHg) Pressure (mb)
Sea Level 29.92 1013
1,000 ft 28.86 977
5,000 ft 24.89 843
10,000 ft 20.58 697
18,000 ft 14.94 506
29,000 ft 8.89 301

Tips for Using the Converter

  • Select your source unit from the "From" dropdown
  • Select your target unit from the "To" dropdown
  • Enter a value and see instant conversion results
  • Click "Standard Pressure" to quickly convert 29.92 inHg
  • Use "Swap Units" to reverse the conversion direction
  • Values are automatically rounded to appropriate decimal places
  • The converter prevents selecting the same unit for both fields