Cups (FDA) to gills (US) conversion calculator above calculates how many gills (US) are in 'X' cups (FDA) (where 'X' is the number of cups (FDA) to convert to gills (US)). In order to convert a value from cups (FDA) to gills (US) simply type the number of cups (FDA) to be converted to gills (US) and then click on the 'convert' button.