Recipe scaler
Sponge Cake Calculator
Use this sponge cake calculator to scale my favourite 8-inch sponge recipe up or down for a different round cake size and layer count.
Base recipe: Victoria Sponge Cake 8in / 20cm round, 2 layers.
Read the full sponge cake recipe walkthrough and method notes.
Scaled recipe
Sponge
Filling
Bake time guide
Finish with a light dusting of icing sugar to serve.
Method (same process at any size)
- Preheat to 170C fan / 180C conventional. Grease and line tins (base and sides).
- Cream very soft butter and caster sugar for 5 to 7 minutes until pale and fluffy.
- Beat eggs in a jug, then add gradually while mixing. If the mix curdles, fold in a spoon of flour.
- Sift and fold in self-raising flour, baking powder, and salt gently with a spatula.
- Add vanilla and enough milk for a slow dropping consistency.
- Divide batter evenly between tins. Bake until golden, springy, and a skewer comes out clean.
- Cool fully. Fill with jam and whipped cream, then dust with icing sugar.
Bake time starts around 25 to 30 minutes for the base 8 inch 2-layer recipe and will vary with layer depth, oven, and tin material.
Planning a party cake?
If you want this sponge covered in buttercream for a celebration or birthday cake, use the Quick Round Cake Buttercream Calculator for a quick estimate. If you want more exact sizing for a custom finish, use the Custom Shape Cake Buttercream Calculator.