Millimeters of Mercury to Atmospheres Converter

To convert a measurement in millimeters of mercury to atmospheres, multiply the value by 0.001315789661. The conversion factor comes from the relationship between both units and the pascal.

For example, to convert 5 mmHg to atmospheres: 5 × 0.001315789661 = 0.006578948306 atm.

A millimeter of mercury (mmHg) is a unit of pressure equal to the pressure exerted by a one-millimeter-high column of mercury, about 133.32 pascals. Derived from early mercury barometers, the mmHg is nearly identical to the torr. It remains the standard unit for blood pressure and other physiological measurements in medicine worldwide.

Common uses of millimeters of mercury include: Blood pressure readings (systolic/diastolic); Intraocular and intracranial pressure; Barometric pressure in medicine; Vacuum and gas-pressure measurement.

A standard atmosphere (atm) is a unit of pressure defined as exactly 101,325 pascals, approximating average sea-level air pressure. Defined by the International Union of Pure and Applied Chemistry as a reference pressure, the atmosphere is widely used in chemistry and physics to describe conditions relative to sea level.

Common uses of atmospheres include: Chemistry reference conditions (STP); Diving and hyperbaric medicine; Physics gas-law calculations; Describing high-pressure environments.

Medical and scientific work spans both units. Barometric pressure is often quoted in mmHg while chemistry problems reference atmospheres, so knowing that 760 mmHg equals exactly one atmosphere bridges physiology, weather, and gas-law calculations.

Here are some common values converted:

1 mmHg = 0.001315789661 atm 5 mmHg = 0.006578948306 atm 10 mmHg = 0.013157896611 atm 50 mmHg = 0.065789483057 atm 100 mmHg = 0.131578966114 atm