Cooks should note that, in most US recipes, dry measurements are made by volume rather than by mass. This can be confusing to people who are used to measuring ingredients in metric, since 1 cup of flour does not have the same mass as 1 cup of granulated sugar — this volume of flour weighs 120 grams, while a cup of sugar weighs 200 grams. Many cookbooks and online recipe sites provide conversions for most common ingredients.