How Much Buttercream for an 8 Inch Cake?
About 5.5 cups (1189 g) of buttercream fills, crumb-coats and covers a three-layer, 4 inch tall 8 inch round cake with a smooth finish. Allow 3.3 cups for a thin, naked finish and 9 cups if you are piping rosettes or ruffles.
You need about1189 g · 5.5 cups
For an 8 inch round, 4 in tall, three layers filled, smooth finish.
By finish
| Finish | Grams | Cups |
|---|---|---|
| Thin Coat Crumb coat / naked cake | 702 g | 3.3 |
| Medium Standard smooth finish | 1189 g | 5.5 |
| Thick Generous frosting layer | 1621 g | 7.5 |
| Piped / Textured Rosettes, ruffles, etc. | 1945 g | 9 |
By height and layers
| Cake | Grams | Cups |
|---|---|---|
| Two layers, 4 in tall | 951 g | 4.4 |
| Three layers, 4 in tall | 1189 g | 5.5 |
| Four layers, 6 in tall | 1664 g | 7.7 |
What to make
For about 1189 g of American-style buttercream (a 1 : 2 butter to icing sugar recipe), beat together:
- 387 g butter, softened — about 1.75 cups
- 746 g icing (powdered) sugar — about 6.25 cups
- 44 ml milk
- 11 tsp vanilla extract
Beat the butter until pale, add the sugar in two or three goes, then the milk and vanilla. Make it the day before if you like — bring it back to room temperature and beat again before using.
How the amount is worked out
The calculator measures the surface you are covering — the top, the sides and one filling layer between each sponge — and multiplies it by how thickly each finish is spread. It is calibrated against published amounts: an 8 inch two-layer cake needs about 4 to 4.5 cups to fill, crumb-coat and finish. Make a little extra for the bowl and the spatula.
Other cake sizes
Topping it?
An 8 inch cake takes a 7.5 in (191 mm) edible image. See the 8 inch cake size guide, or open that size in the topper editor — free to design.
Frequently Asked Questions
How much buttercream to crumb coat an 8 inch cake?
About 2 cups (421 g) for a thin crumb coat over the top and sides of a 4 inch tall 8 inch cake, not counting the filling.
How much buttercream for a two-layer 8 inch cake?
About 4.4 cups (951 g) to fill between the two layers and cover the cake with a smooth finish.
How much icing sugar do I need for buttercream for an 8 inch cake?
About 746 g (6.25 cups) of icing (powdered) sugar with 387 g of butter, for the smooth-finish amount of about 1189 g of buttercream.
Worked out with the same model as the buttercream calculator, so this page and the calculator always agree. CakeyTops calculators are free to use with no account.