Millimeters of mercury to centimeters of mercury converter on this page calculates how many centimeters of mercury are in 'X' millimeters of mercury (where 'X' is the number of millimeters of mercury to convert to centimeters of mercury). In order to convert a value from millimeters of mercury to centimeters of mercury (from mmHg to cmHg) just type the number of mmHg to be converted to cmHg and then click on the 'convert' button.