Baking Pan Conversion Calculator

Compare baking pan sizes

Select the original and replacement pan shapes, then enter their inside top dimensions. The calculator compares surface areas and estimates the batter multiplier needed to preserve approximately the same depth.

For example, moving from an 8-inch round pan to a 9-inch round pan increases area by about 26.6%, so a similar-depth batch would use about 1.27 times the batter.

What the depth comparison means

Using the same amount of batter in a larger-area pan makes a shallower layer. Using it in a smaller-area pan makes a deeper layer. Depth can influence how quickly the center cooks relative to the edges.

The calculation uses top area only. It does not verify pan capacity, wall angle, usable depth, or whether the batter will fit without overflowing.

Baking time and safety

Do not multiply baking time by the batter factor. Start checking based on the original recipe’s guidance, the observed depth, and reliable doneness indicators. Follow food-safety temperature guidance where applicable.

A batter multiplier above 1 means more batter, so check the fill level before baking. Most batters should not fill a pan beyond about two-thirds of its usable depth, and cake batters that rise substantially often need less. Overflow onto a hot oven floor is a smoke and fire hazard, not only a cleaning problem. If the multiplier does not fit the replacement pan, bake in more than one pan rather than overfilling.