Found said formula on below site.
http://braukaiser.com/wiki/index.php/Carbonation_Tables
Rearranging for pressure (in bars)
CBeer = 1.96 * Vol (convert volume to g/L)
Temp = temperature in degrees C
Bar = (Cbeer / (2.71828182845904 ^ (-10.73797 + (2617.25 / (Temp + 273.15)))) / 10) - 1.013
kPa = Bar * 100
PSI = kPa * 0.145038
http://braukaiser.com/wiki/index.php/Carbonation_Tables
Rearranging for pressure (in bars)
CBeer = 1.96 * Vol (convert volume to g/L)
Temp = temperature in degrees C
Bar = (Cbeer / (2.71828182845904 ^ (-10.73797 + (2617.25 / (Temp + 273.15)))) / 10) - 1.013
kPa = Bar * 100
PSI = kPa * 0.145038
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