Convert Millimeter of mercury to Atmosphere

One mmHg equals 0.001315789661 atm. This converter allows you to easily convert between Millimeter of mercury and Atmosphere in real time.

Formula

mmHg × 0.001315789661 = atm

Example: 1 mmHg = 0.001315789661 atm

What is Millimeter of mercury?

The millimeter of mercury is a unit of pressure based on the height of a mercury column, equal to approximately 133.3 pascals. It is the universal standard for reporting blood pressure in medicine: normal blood pressure is below 120 mmHg systolic and 80 mmHg diastolic. The unit originates from Torricelli's 1643 experiment, which showed that atmospheric pressure supports a mercury column of about 760 mm. One mmHg is nearly identical to one torr.

What is Atmosphere?

The standard atmosphere is a unit of pressure defined as exactly 101,325 pascals. It approximates the average atmospheric pressure at sea level on Earth. In diving, pressure increases by roughly 1 atm for every 10 meters of water depth, so at 30 meters the total pressure is about 4 atm. In chemistry, standard conditions for gases are defined at 0 degrees Celsius and 1 atm, making it a fundamental reference in thermodynamics and gas law calculations.