Decibars to centimeters of water conversion calculator shown above calculates how many centimeters of water are in 'X' decibars (where 'X' is the number of decibars to convert to centimeters of water). In order to convert a value from decibars to centimeters of water (from dbar to cmH2O) type the number of dbar to be converted to cmH2O and then click on the 'convert' button.