Pan Size & Bake Time Converter
Only have a 9×13 when the recipe calls for two 9" rounds? Pick your pans and get an adjusted bake time and temperature instantly.
Based on the pans' surface area (a 84% larger area change). Start checking for doneness a few minutes early — always confirm with a toothpick or thermometer.
9×13" Rectangular has a lot more surface area than 9" Round — your batter will spread very thin. Consider a 1.5x recipe, or use a smaller pan instead.
How the Adjustment Works
Compare surface area
We look at the baking surface area of both pans — a 9" round and a 9×13 rectangular can differ by 80% or more.
Adjust temperature
A larger, shallower pan bakes hotter at the edges before the center sets — so we trim the temperature when the area jumps up.
Adjust time
Thinner batter bakes faster, thicker batter takes longer. Time scales with the ratio of the two pans' areas.
Common Pan Sizes & Volume
| Pan | Surface Area | Approx. Volume |
|---|---|---|
| 6" Round | 28.3 in² | 4 cups |
| 8" Round | 50.3 in² | 6 cups |
| 9" Round | 63.6 in² | 8 cups |
| 10" Round | 78.5 in² | 11 cups |
| 9" Springform | 63.6 in² | 8 cups |
| 10" Springform | 78.5 in² | 11 cups |
| 8" Square | 64 in² | 8 cups |
| 9" Square | 81 in² | 10 cups |
| 9×13" Rectangular | 117 in² | 14 cups |
| Half Sheet Pan (13×18") | 234 in² | 28 cups |
| 8×4" Loaf | 32 in² | 6 cups |
| 9×5" Loaf | 45 in² | 8 cups |
| 10-Cup Bundt | 75 in² | 10 cups |
| 12-Cup Bundt | 85 in² | 12 cups |
| 12-Cup Muffin Tin (standard) | 36 in² | 6 cups |
Frequently Asked Questions
Is this tool really free?
Yes — completely free, no sign-up needed, and there's no usage limit since it's pure math with no AI involved.
How accurate is the adjustment?
It follows the standard baking heuristic (adjust time by the area ratio, trim temperature for shallower pans) that most baking references recommend. Always check doneness early with a toothpick or thermometer — actual ovens and batters vary.
What if the pans are very different sizes?
If the area difference is too large, batter can spread too thin or overflow the pan. We'll show a warning and suggest scaling the recipe or filling the pan only partway.
Does this work for bread, casseroles, and other bakes, not just cakes?
The area-based time adjustment is a reasonable starting point for any baked good, but delicate bakes (soufflés, custards) are more sensitive to pan depth — check them extra early.
What is Vidcipe?
Vidcipe is the full app — it extracts complete structured recipes (ingredients + step-by-step instructions + tips + full nutrition) from any cooking video. This pan converter is a free companion tool.