Baking Pan Size Converter
Switch cake, brownie, bar, and quick bread recipes between round, square, and rectangular pans. Compare pan area, scale batter, and get a practical baking-time cue before you preheat.
Convert your recipe pan
Enter the pan your recipe uses and the pan you want to use. The converter estimates how much batter or recipe quantity you need.
Your pan is larger, so the same batter will be shallower and may bake a little faster.
How pan size conversion works
Most pan swaps are based on surface area. A pan with 25% more area needs about 25% more batter to keep the same depth. If you keep the recipe amount the same in a larger pan, the batter spreads thinner and usually bakes faster.
This is especially helpful for layer cakes, sheet cakes, brownies, blondies, cornbread, snack cakes, and loaf-style bakes where pan depth affects texture.
Common pan equivalents
| Pan | Approx. area | Close swap |
|---|---|---|
| 8-inch round | 50 sq in | 7-inch square |
| 9-inch round | 64 sq in | 8-inch square |
| 9-inch square | 81 sq in | 10-inch round |
| 9×13 rectangle | 117 sq in | Two 9-inch rounds |
Baking pan conversion FAQ
What is the best substitute for a 9-inch round cake pan?
An 8-inch square pan is a very close substitute because it has about the same surface area. Watch the bake closely because pan material and batter depth still matter.
Can I double a recipe for a 9×13 pan?
It depends on the original pan. A 9×13 pan is about 117 square inches, roughly 1.8 times a 9-inch round pan and about 1.45 times a 9-inch square pan.
Should I fill a cake pan to the top?
No. Many cakes need room to rise. A common rule is to fill cake pans about halfway to two-thirds full unless your recipe says otherwise.