Pressure Converter
Convert pascals, bar, psi, atmospheres, mmHg and inHg.
1 bar equals 14.5038 pounds per square inch
About pressure units
Pressure is force per unit area, measured in pascals in SI. Everyday use is fragmented: tyres are set in psi or bar, weather is reported in hectopascals or inches of mercury, and blood pressure is measured in millimetres of mercury — a unit that survives because of the mercury column manometer.
Unit conversion preserves the pressure reference. Gauge pressure and absolute pressure are different readings; changing between them also needs the ambient pressure. Mercury and water-column units use the conventions stated in their unit notes.
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All units
Compare unit values in the base unit. Numbers are rounded to 8 significant digits; conventions and assumptions appear beside the units.
| Unit | Symbol | 1 unit in Pa |
|---|---|---|
| pascal | Pa | 1 |
| kilopascal | kPa | 1,000 |
| megapascal | MPa | 1,000,000 |
| hectopascal | hPa | 100 |
| bar | bar | 100,000 |
| millibar | mbar | 100 |
| standard atmosphere | atm | 101,325 |
| pound per square inch | psi | 6,894.7573 |
| kilopound per square inch | ksi | 6,894,757.3 |
| torr | Torr | 133.32237 |
| millimeter of mercuryAlmost identical to the torr, but defined separately. This uses conventional mmHg, not a temperature-specific mercury-column realization. | mmHg | 133.3224 |
| inch of mercury | inHg | 3,386.389 |
| inch of waterThis uses conventional inH₂O, not the temperature-specific water-column units at 4 °C or 60 °F. | inH₂O | 249.0889 |
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