Same depth is assumed. Measure pans across the top, inside edge to inside edge.
Multiply every ingredient by
How pan conversion works
Batter fills a pan by area. If two pans have the same depth, the amount of batter you need changes by the ratio of their areas. A 9 × 13 inch pan has 117 square inches; an 8 × 8 inch pan has 64. So a recipe written for 9 × 13 needs 64 ÷ 117 = about 0.55 times every ingredient to fill an 8 × 8 pan to the same depth.
Round pans use the area of a circle: π × radius². A 9 inch round is about 64 square inches, almost exactly the same as an 8 inch square, which is why those two pans are so often swapped.
Adjusting the baking time
When the batter sits at the same depth, the baking time stays close to the original. When you use the same amount of batter in a bigger pan, the layer is thinner and bakes faster; in a smaller, deeper pan it takes longer, and the centre may need the oven 25°F lower so the edges don't overbake. Either way, start checking 5 to 10 minutes before the recipe's time with a toothpick in the centre.
Leave about a third of the pan's height empty for cakes and quick breads to rise. Brownies and bars can fill a pan about halfway.
Pan sizes by area
Square inches of baking surface.
| Pan | Area (sq in) |
|---|---|
| 8 × 8 inch square | 64 |
| 9 × 9 inch square | 81 |
| 11 × 7 inch baking dish | 77 |
| 9 × 13 inch pan | 117 |
| 10 × 15 inch jelly roll pan | 150 |
| 13 × 18 inch half sheet | 234 |
| 6 inch round | 28 |
| 8 inch round | 50 |
| 9 inch round | 64 |
| 10 inch round | 79 |
| 12 inch round | 113 |
| 9 inch springform | 64 |
| 10 inch springform | 79 |
| 8½ × 4½ inch loaf | 38 |
| 9 × 5 inch loaf | 45 |
Common pan swaps
Multiply the recipe by this amount.
| Recipe pan | Your pan | Multiply by |
|---|---|---|
| 9 × 13 inch pan | 8 × 8 inch square | ×0.55 |
| 9 × 13 inch pan | 9 inch round | ×0.54 |
| 9 × 13 inch pan | 10 × 15 inch jelly roll pan | ×1.28 |
| 8 × 8 inch square | 9 × 9 inch square | ×1.27 |
| 8 × 8 inch square | 9 inch round | ×0.99 |
| 9 inch round | 8 inch round | ×0.79 |
| 8 inch round | 6 inch round | ×0.56 |
| 9 × 5 inch loaf | 8½ × 4½ inch loaf | ×0.85 |
| 9 × 9 inch square | 9 × 13 inch pan | ×1.44 |
| 9 inch round | 9 × 13 inch pan | ×1.84 |
Pan size questions
Can I use two 8 inch square pans instead of a 9 × 13?
Yes. Two 8 × 8 pans give 128 square inches, slightly more than a 9 × 13 (117), so the batter will be a little thinner. Divide it evenly and start checking about 5 minutes early.
What pan is half of a 9 × 13?
An 8 × 8 or a 9 inch round each hold a little more than half, so halve the recipe and expect a slightly thinner layer, or use 0.55 of every ingredient for the same depth.
Is an 8 inch round the same as an 8 inch square?
No. An 8 inch round has about 50 square inches, while an 8 inch square has 64, about 28% more. A recipe for an 8 inch square needs about 0.79 times the ingredients for an 8 inch round.
How do I convert a recipe for a loaf pan to muffins?
A 9 × 5 loaf of quick bread batter fills about 12 standard muffin cups. Bake at the same temperature, but start checking at around 18 to 20 minutes instead of an hour.
Do glass and metal pans bake the same?
Glass and dark metal pans absorb heat faster. Lower the oven by about 25°F for glass, and check a few minutes early.