Convert any pressure unit
Pick any two units and convert between them: pascals, kilopascals, bars, standard atmospheres, pounds per square inch (PSI) and millimetres of mercury. The result updates as you type, and negative values are accepted because gauge pressure can be below atmospheric.
Every unit is defined against the pascal. The bar is exactly 100,000 Pa and the standard atmosphere exactly 101,325 Pa.
Units at a glance
| Unit | Symbol | Size |
|---|---|---|
| pascals | Pa | The base unit for pressure. |
| kilopascals | kPa | 1 kilopascal = 1,000 pascals |
| bars | bar | 1 bar = 100,000 pascals |
| atmospheres | atm | 1 atmosphere = 101,325 pascals |
| pounds per square inch | psi | 1 pound per square inch = 6,894.75729317 pascals |
| millimetres of mercury | mmHg | 1 millimetre of mercury = 133.322387415 pascals |
Gauge and absolute pressure
Tyre and boiler gauges usually show gauge pressure, which is measured relative to the atmosphere around you. Absolute pressure adds about one atmosphere. This converter changes units only: it does not add or remove atmospheric pressure.
mmHg and torr
Blood pressure and barometers use millimetres of mercury. The torr is defined as 1/760 of a standard atmosphere and differs from the conventional mmHg by less than two parts in ten million.