8" round to 9" round
| Recipe pan | Your pan | |
|---|---|---|
| Pan | 8" round | 9" round |
| Area | 50.3 sq in | 63.6 sq in |
| Capacity | 7 cups | 8.8 cups |
| Multiply by | 1.27 |
- One inch of diameter looks small, but it adds 27% more batter.
- The batter stays the same depth, so keep the oven at the recipe temperature. A wider cake can finish a few minutes sooner, so check early.
- A 3 egg recipe needs about 3.8 eggs, so use 4.
- The same factor works for an 8 inch square to a 9 inch square, because both ratios are 81 to 64.
Example: a plain butter cake
This is a sample ingredient list scaled for this swap. Paste your own recipe in the tool above to scale it.
| Recipe says | Use |
|---|---|
| 2 cups all-purpose flour | 2 1/2 cups all-purpose flour |
| 1 1/2 cups sugar | 1 7/8 cups sugar |
| 1/2 cup (1 stick) butter | 5/8 cup (1 1/4 sticks) butter |
| 3 large eggs | 4 large eggs |
| 3/4 cup milk | 1 cup milk |
| 2 tsp baking powder | 2 1/2 tsp baking powder |
Bake time and temperature
For a recipe that bakes 35 minutes at 350°F: start checking at 33 minutes and expect it done by 37, at 350°F.
The batter depth is close to the recipe pan. Keep the same oven temperature and check at about the same time.
Fill any pan no more than two thirds full. Bake leftover batter as cupcakes.
Questions about this swap
How much more batter does a 9 inch round need than an 8 inch round?
About 27% more. Multiply every ingredient by 1.27. A cup of sugar becomes 1 1/4 cups.
Do I change the bake time for a 9 inch pan?
Not much. The batter depth stays the same. Start checking a few minutes early and test with a toothpick.