Baking Pan Size Converter
Ever found a recipe you wanted to make but didn't have the right baking pan?
Whether you're preparing cornbread, a family cake, brownies, cobbler, or a favorite casserole, changing pan sizes can affect how much batter you need and how evenly your dish cooks.
Our Baking Pan Size Converter helps you compare common pan sizes and estimate how to adjust your recipe.
Baking Pan Size Converter · heritagekitchen.food
Your results
Your Pan Conversion
Original pan
117 sq in surface
13 x 9 in rectangle
Replacement pan
64 sq in surface
8 x 8 in square
Surface-area comparison
Replacement compared with original
About 55%
Suggested starting multiplier
× 0.55
If your replacement pan has about 55% of the original pan's surface area, consider using about half the recipe to keep a similar batter depth. Treat this as a starting point, not a guarantee.
- Using the full recipe in this smaller pan would make deeper batter, which usually needs longer baking — and could overflow.
- Fill pans no more than about two-thirds full.
- Glass, dark metal and cast iron brown faster than light metal.
- Start checking early and test for doneness rather than relying on the original baking time.
Kitchen wisdom
Kitchen Know-How
Cornbread: skillet or square pan
A 10-inch skillet has about 79 square inches of surface, while an 8-inch square pan has 64. A recipe written for the square pan will bake thinner in the skillet, and a hot cast-iron skillet browns the crust faster — so start checking early.
Brownies in a different pan
A 9x13 pan has about 117 square inches, nearly double an 8-inch square at 64. Doubling an 8-inch recipe fits a 9x13 at about the same thickness, but thicker or thinner brownies will need their own baking check.
Round cakes vs a sheet cake
Two 9-inch rounds together cover about 127 square inches, close to one 9x13 pan. The area matches, but a single large pan bakes differently at the center, so test with a toothpick rather than trusting the clock.
Cobbler and casserole portions
Surface area also tells you how many servings to expect. An 8-inch square holds roughly half of a 9x13, so plan for about half as many portions when you cut it the same size.