Cake Pan Converter
Swap a recipe's cake pan for the one you own and find out how much batter to make, with the recipe scaled for you.
Your 13 × 9 in pan holds 2.33 times as much as the 8 in round pan. Make 2.33 times the recipe for a cake of the same height, or keep the recipe and expect a cake 43% as deep that bakes faster.
Both pans to scale
- Recipe pan: 8 in round, 50.3 sq in
- Your pan: 13 × 9 in, 117 sq in
Seen from above at one scale, your 13 × 9 in pan covers 117 sq in and the 8 in round pan 50.3 sq in, 2.33 times as much. Filled to the rim, your pan holds about 16.2 cups.
Fine-tune your pan
With different depths the factor compares volumes, so a deeper pan needs more batter.
Your recipe, scaled
Scaled by 2.33
| Ingredient | Recipe | Scaled |
|---|---|---|
| cups flour | 2 1/4 | 514 |
| cups sugar | 1 1/2 | 312 |
| eggs | 3 | 7 |
| cup milk | 1 | 238 |
| cup butter | 1/2 | 118 |
| tsp baking powder | 2 | 458 |
Cups, spoons and counts round to the nearest eighth; grams and milliliters to whole numbers.
Same batter, another shape
A 7.1 in square pan holds the same as the 8 in round pan, so the recipe needs no scaling.
Pans are sold in whole or half sizes, so pick the nearest one and adjust the batter.
Common pans against an 8 in round
| Pan | Area | Use | |
|---|---|---|---|
| 6 in round | 28.3 sq in | 0.56 | |
| 8 in round | 50.3 sq in | 1.00 | |
| 9 in round | 63.6 sq in | 1.27 | |
| 10 in round | 78.5 sq in | 1.56 | |
| 8 in square | 64 sq in | 1.27 | |
| 9 in square | 81 sq in | 1.61 | |
| 11 × 7 in | 77 sq in | 1.53 | |
| 13 × 9 in | 117 sq in | 2.33 | |
| 8.5 × 4.5 in loaf | 38.3 sq in | 0.76 | |
| 9 × 5 in loaf | 45 sq in | 0.90 | |
| 10 in bundt | 71.5 sq in | 1.42 |
Multiply by compares base areas, as if both pans were filled to the same depth.
Baking time and temperature
- Fill cake pans
- 12 to 23 full
- Most pans
- 350 °F (about 175 °C)
- The largest pans
- 325 °F (about 160 °C)
- Use a heating core
- 3 in deep, 12 in across
Unscaled, the batter sits thinner in your pan, so it bakes faster: start checking well before the recipe time. Guidance from Wilton's baking guide.
How it's worked out
A cake pan holds batter over its base. If two pans are filled to the same depth, the batter they need is in the same ratio as their base areas. So the tool works out each pan's area and divides yours by the recipe's.
A round pan's area is π × radius², so an 8 inch round covers 50.3 square inches and a 9 inch round 63.6. One extra inch across adds about a quarter more cake. A square is side times side, so an 8 inch square covers 64 square inches, about the same as the 9 inch round. Rectangles and loaf pans are length times width.
Bundt and tube pans lose the middle to the tube. The tool takes the tube as 30% of the diameter and does not model fluted sides, so treat a bundt result as a close guide. If you enter different depths for the two pans, the tool compares volumes instead, because a deeper pan holds more batter over the same base.
The recipe card multiplies the amount at the start of each line. Cups, spoons and counts round to the nearest eighth, the smallest mark on most measuring sets. Grams and milliliters round to whole numbers.
Worked examples
Lena's round cake in a 9 by 13 pan
Lena's recipe is for an 8 inch round, but she wants a sheet cake for a party. The 13 by 9 pan covers 117 square inches against 50.3, so she multiplies by 2.33. Her 94 cups of flour become 5 14 cups and 3 eggs become 7. If she made the recipe as written, the batter would sit only 43% as deep and bake much faster. Open this example in the tool
A sheet cake recipe as round layers
A 9 by 13 recipe covers 117 square inches, and one 9 inch round covers 63.6. Each round takes 0.54 of the recipe, so the batter fills 1.84 rounds. Split between two 9 inch pans, the layers come out a little thinner than the sheet cake, which suits a layer cake. One round pan 12.2 inches across would hold it all. Open this example in the tool
A European recipe for a 20 cm round
Your pan is 23 cm across. Three centimeters sounds small, but the area grows with the square of the diameter, so you multiply by 1.32. Flour of 94 cups becomes 3 cups and 250 g of butter becomes 331 g. Open this example in the tool
Reading your result
The big number is what to multiply every ingredient by. Above 1, your pan is bigger and needs more batter; under 1, it needs less. Between about 0.95 and 1.05 the pans are close enough to use the recipe as written.
The tile for unscaled batter depth tells you what happens if you do not scale. A thinner layer bakes faster, so start checking well before the recipe time. A deeper layer needs longer, and the edges can dry out before the middle sets. Wilton's baking guide fills cake pans half to two-thirds full, bakes most pans at 350 °F and its largest at 325 °F, and uses a heating core in pans 3 inches deep and 12 inches across or more.
The common pans table compares the recipe pan with the sizes most kitchens have. Press Use on any row to make it your pan and see the drawing, scaled recipe and notes change.
Common mistakes
- Scaling by the diameter. A 10 inch round is not 25% bigger than an 8 inch round; it holds about 56% more batter, because area grows with the square of the size.
- Measuring the outside of the pan. Measure across the inside of the top edge. Many pans flare outward, and measuring over the rim makes the pan look bigger than it bakes.
- Rounding eggs too far. For 3.8 eggs, use 4, or beat 4 eggs and weigh out the part you need: a large egg is about 50 g without the shell.
- Keeping the same time. The oven time follows the batter depth, not the recipe. Test with a skewer in the middle; it should come out with a few moist crumbs.
- Overfilling a deep pan. More batter in a small pan can rise over the rim. Keep to two-thirds full and bake any extra as cupcakes.
Questions people ask
Sources
Maintained by Anil ShahUpdated October 28, 2026Checked against 12 reference values