Sixty grams of standard butter is replaced by 48 g of oil for an exact fat match. That is approximately 53 ml of vegetable or canola oil.
The exact calculation
Standard butter is about 80% fat. Multiply the butter weight by 0.80:
60 g butter × 0.80 = 48 g oil
This preserves the amount of fat rather than treating butter and oil as equal products. Use the butter to oil converter if you need tablespoons, cups or a different oil.
Measuring 48 g oil
The cleanest method is to place the mixing bowl on a scale, tare it and pour until the display reaches 48 g. If measuring by volume, use about 53 ml vegetable oil.
Three and a half US tablespoons are close, but spoon measurements introduce more variation than a scale. An Australian tablespoon is larger than a US tablespoon and should not be treated as the same unit.
What happens to the recipe
Oil removes the water and milk solids that were present in butter. Sixty grams of butter contains roughly 10 g water, although the exact figure varies by brand.
For a cake or quick bread, add up to two teaspoons of milk or water if the batter looks unusually thick. Skip the adjustment when fruit, yoghurt or another moist ingredient already keeps the batter loose.
Choose recipes that suit liquid fat
This conversion works well in muffins, loaf cakes and brownies. It is not enough for pastry, shortbread or creamed cookies, where butter’s solid state and ability to trap air are part of the recipe’s structure.
Use 48 g oil as the accurate starting point, then judge whether the original method can tolerate a liquid fat.