Gallon-atmosphere (US) to gallon-atmosphere (UK) conversion calculator shown above calculates how many gallon-atmosphere (UK) are in 'X' gallon-atmosphere (US) (where 'X' is the number of gallon-atmosphere (US) to convert to gallon-atmosphere (UK)). In order to convert a value from gallon-atmosphere (US) to gallon-atmosphere (UK) (from gal atm to gal atm) type the number of gal atm to be converted to gal atm and then click on the 'convert' button.