Pressure Unit Converter
The pressure unit converter allows you to convert between commonly used pressure measurements such as PSI, pascals, bars, atmospheres, and torr. This tool is useful for engineers, meteorologists, divers, and anyone working with pressure measurements. Select a conversion below or choose from popular pressure unit conversions.
Supported Pressure Units
| Unit | Short Form | Description |
|---|---|---|
| Pascal | Pa | SI derived unit of pressure, N/m² |
| Kilopascal | kPa | 1,000 pascals |
| Megapascal | MPa | 1,000,000 pascals |
| Hectopascal | hPa | 100 pascals, used in meteorology |
| Pounds per Square Inch | psi | Imperial unit, lbf/in² |
| Atmosphere | atm | Standard atmospheric pressure at sea level |
| Torr | torr | 1/760 of an atmosphere, used in vacuum |
| Bar | bar | 100,000 pascals, nearly equal to 1 atm |
| Millibar | mbar | 1/1,000 of a bar, 100 pascals |
| Millimeters of Mercury | mmHg | Pressure exerted by 1mm column of mercury |
| Millimeters of Water | mmH2O | Pressure exerted by 1mm column of water |
| Centimeters of Water | cmH2O | Pressure exerted by 1cm column of water |
Popular Pressure Conversions
How Pressure Unit Conversion Works
Pressure units are converted using fixed mathematical ratios based on the definition of pressure as force per unit area.
For example, 1 atmosphere equals 101,325 pascals or 14.7 PSI, and 1 bar equals 100,000 pascals.
Our pressure converter uses accurate conversion factors to ensure precise results for engineering, meteorology, and scientific applications.
Common Use Cases
- Tire pressure measurement
- Weather forecasting and barometric pressure
- HVAC system specifications
- Scuba diving depth calculations
- Vacuum system measurements
Frequently Asked Questions
How accurate is the pressure unit converter?
Our converter uses precise conversion factors based on international standards. Results are accurate to multiple decimal places, suitable for professional use in engineering, meteorology, and scientific research.
What is a pascal?
A pascal (Pa) is the SI derived unit of pressure, defined as one newton per square meter. It’s named after Blaise Pascal, French mathematician and physicist.
How many PSI is one atmosphere?
1 atmosphere (atm) equals approximately 14.696 PSI (pounds per square inch). This is the average atmospheric pressure at sea level.
What’s the difference between bar and atmosphere?
A bar equals 100,000 pascals, while an atmosphere equals 101,325 pascals. They’re very close - 1 bar ≈ 0.987 atm. The bar is slightly more convenient as a round number.
What is the proper tire pressure?
Typical car tire pressure ranges from 30-35 PSI (207-241 kPa or 2.07-2.41 bar). Always check your vehicle’s specific recommendations, usually found on a sticker inside the driver’s door or in the owner’s manual.
What is a torr?
A torr is a unit of pressure equal to 1/760 of an atmosphere, approximately 133.32 pascals. It’s named after Evangelista Torricelli and is commonly used in vacuum measurements and medicine.
How is barometric pressure measured in weather?
Weather reports typically use millibars (mbar) or hectopascals (hPa) - these are equivalent units (1 mbar = 1 hPa). Standard atmospheric pressure is about 1013 mbar. In the US, inches of mercury (inHg) is also common.
What does mmHg mean?
mmHg (millimeters of mercury) represents the pressure that can support a column of mercury 1mm high. It’s commonly used in medicine for blood pressure measurements. 1 mmHg ≈ 133.32 Pa.