Cake Pan Size Converter
Only have a different pan? Pick what the recipe calls for and what you've got — I'll tell you how to scale the ingredients.
Common pan sizes (by area)
| Pan | Area |
|---|---|
| 6" round | 28.3 sq in |
| 7" round | 38.5 sq in |
| 8" round | 50.3 sq in |
| 9" round | 63.6 sq in |
| 10" round | 78.5 sq in |
| 8×8" square | 64 sq in |
| 9×9" square | 81 sq in |
| 11×7" rectangle | 77 sq in |
| 9×13" rectangle | 117 sq in |
| 10×15" jelly roll | 150 sq in |
| 8.5×4.5" loaf | 38.3 sq in |
| 9×5" loaf | 45 sq in |
This scales by pan area (and so by batter volume). For big jumps, also adjust bake time and check doneness — depth changes how heat reaches the center.
Frequently asked questions
Can I use a 9×13 pan instead of two 9-inch round pans?
Almost — a 9×13 pan holds about 117 sq in of batter and two 9-inch rounds hold about 127 sq in combined, so a two-layer 9-inch recipe fits a single 9×13 as a slightly thinner sheet cake. Keep the temperature the same and start checking a few minutes early.
How do I swap a round pan for a square pan?
Compare their areas. An 8-inch square (64 sq in) holds about the same as a 9-inch round (64 sq in), so you can swap those two with no change to the recipe. An 8-inch round is smaller (50 sq in), so moving up to an 8-inch square gives you a thinner bake unless you scale the recipe up.
Do I change the bake time when I change pan size?
Yes. A wider, shallower pan bakes faster; a smaller, deeper pan bakes slower. Leave the oven temperature alone and adjust the time — start checking 5–10 minutes before the original time and go by a clean skewer, not the clock.
How full should I fill a cake pan?
About halfway to two-thirds full. Overfilling makes the batter dome or spill and undercook in the middle; underfilling gives a flat, dry cake. Matching the pan's area to the recipe (what this converter does) keeps the depth right.
Why scale by area instead of by diameter?
Because batter fills area, not width. A 10-inch round isn't 25% bigger than an 8-inch round — it's about 56% bigger, because area grows with the square of the radius. Scaling by area is what keeps the batter depth, and therefore the bake time, consistent.