Grams per gallon (UK) to grams per cubic decimeter conversion calculator above calculates how many grams per cubic decimeter are in 'X' grams per gallon (UK) (where 'X' is the number of grams per gallon (UK) to convert to grams per cubic decimeter). In order to convert a value from grams per gallon (UK) to grams per cubic decimeter (from g/gal to g/dm³) just type the number of g/gal to be converted to g/dm³ and then click on the 'convert' button.