Baking Pan Size Converter
Find equivalent baking pan sizes when substituting round, square, and rectangular pans.
Compare volumes in cups to adjust batter and baking time correctly.
Enter your pan dimensions to calculate area, then compare with another pan size.
Pan A (your recipe's pan)
Pan B (the pan you have)
Convert a pan measurement between inches and centimeters.
When substituting baking pans, the key is matching the area of the pan. Pans with similar areas will hold the same amount of batter.
Area formulas:
- Round pan: area = π × (diameter / 2)²
- Square pan: area = side × side
- Rectangular pan: area = length × width
Common pan equivalents (by area):
| Pan | Size (in) | Size (cm) | Area (in²) |
|---|---|---|---|
| Round | 8" dia | 20 cm | 50.3 |
| Square | 7" | 18 cm | 49.0 |
| Round | 9" dia | 23 cm | 63.6 |
| Square | 8" | 20 cm | 64.0 |
| Round | 10" dia | 25 cm | 78.5 |
| Rectangular | 9" × 13" | 23 × 33 cm | 117.0 |
| Round | 12" dia | 30 cm | 113.1 |
Inches to centimeters:
- 1 inch = 2.54 cm
Volume scaling tip: If the pan area differs, adjust the recipe proportionally. New amount = original amount × (new area ÷ original area).
Substitution rules of thumb:
- An 8-inch round pan holds about the same batter as a 7-inch square.
- A 9-inch round is close to an 8-inch square.
- Doubling a recipe? Go up roughly 2 inches in round diameter (8-inch to 10 or 12-inch), not a pan that just looks “twice as big.”
A few things that actually change your results: Fill any pan only halfway to two-thirds full, or the batter climbs over the rim. Swap to a wider pan than the recipe calls for and the batter sits shallower, so it bakes faster; check it 15 to 20% sooner. Go smaller and it runs deep: add time and watch for overflow. The factor people miss is pan color. Dark metal absorbs more heat and browns edges quicker, so drop the oven about 25°F (15°C) when you use one.
How we build and check this converter
This converter runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.
SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.