Full name: millimeter of mercury [0 °C]
Plural form: millimeters of mercury
Alternate spelling: mm of mercury
Category type: pressure
Scale factor: 133.32239
The SI derived unit for pressure is the pascal.
1 pascal is equal to 0.00750061561303 mmHg.
Valid units must be of the pressure type.
You can use this form to select from known units:
I'm feeling lucky, show me some random units
The torr (symbol: Torr) or millimetre of mercury (mmHg) is a non-SI unit of pressure. It is the atmospheric pressure that supports a column of mercury 1 millimetre high. The unit is named after Evangelista Torricelli, Italian physicist and mathematician, for his discovery of the principle of the barometer in 1643.