Cake Pan Converter
Scale a cake recipe from one pan to another without guessing. Enter your original and target pans and get the ingredient multiplier based on pan area, plus practical notes on batter depth and baking time.
Use about 1.27× the recipe
Example recipe scaled by 1.27×
| Ingredient | Original | Scaled |
|---|---|---|
| Flour | 200 g | 253 g |
| Sugar | 200 g | 253 g |
| Butter | 100 g | 127 g |
| Milk | 240 ml | 304 ml |
| Eggs | 3 | 4 (≈ 3.8) |
Eggs are rounded to the nearest whole egg. When you don’t know the exact egg count, treat egg quantities as approximate — they may need rounding up or down.
Scale one of your ingredients
Baking time
The batter layer will be deeper. Consider lowering the temperature slightly and/or baking longer, and test the centre for doneness.
Pan material, batter type and oven calibration can change baking time. Always test doneness.
How the cake pan conversion works
The converter compares the surface area of your two pans, because area is what decides how deep the batter sits and how it bakes. It normalizes every dimension to a common unit (1 inch = 2.54 cm), computes each pan’s area, then divides target area by original area to get a single scale factor.
- Round pan: area = π × (diameter ÷ 2)²
- Square pan: area = side²
- Rectangular pan (and sheet pans): area = width × length
Multiply every ingredient by the scale factor to keep the same batter depth. For example, moving an 8-inch round (≈ 50.3 sq in) recipe to a 9-inch round (≈ 63.6 sq in) gives a factor of about 1.27× — “use about 1.27× the recipe.”
Common cake pan size conversions
| From | To | Scale factor | Note |
|---|---|---|---|
| 8-inch round | 9-inch round | 1.27× | Very common swap — scale up ~27%. |
| 9-inch round | 8-inch round | 0.79× | Scale down ~21%. |
| 8-inch round | 10-inch round | 1.56× | Noticeably bigger — ~56% more. |
| 9-inch round | 10-inch round | 1.23× | Modest step up. |
| 8-inch square | 9-inch round | 0.99× | Almost identical area. |
| 9×13 rectangle | 8-inch square | 0.55× | About half the recipe. |
Round vs square vs rectangular pans
Shapes with the same nominal size hold different amounts. An 8-inch square (64 sq in) has more area than an 8-inch round (≈ 50.3 sq in) — roughly 27% more — because the corners add surface. A quick rule of thumb: a square pan is close to a round pan one inch larger. Rectangular and sheet pans are handled as width × length, so a 9×13 (117 sq in) holds a lot more than most round pans.
When you switch shapes, scale by area (as this tool does) rather than by the nominal number on the pan.
How to adjust baking time
Baking-time changes are directional, not exact:
- Similar area ratio, similar depth: baking time is often close — start checking a couple of minutes early.
- Shallower batter (bigger pan, same recipe): it bakes faster, so check earlier.
- Deeper batter (smaller pan or scaled-up recipe): lower the temperature slightly and/or bake longer.
- Always test doneness with a skewer or thermometer rather than trusting the clock.
Pan material, batter type and oven calibration can change baking time.
FAQ
Can I use a 9-inch pan instead of an 8-inch pan?
Yes, but the batter spreads thinner in the larger pan. A 9-inch round has about 27% more area than an 8-inch round, so the same batter bakes shallower and a little faster — start checking for doneness earlier. To keep the original height, scale the recipe up by about 1.27×.
How do I scale a cake recipe for a different pan?
Work out the area of both pans, then multiply every ingredient by target area ÷ original area. Round pans use π × (diameter ÷ 2)²; square and rectangular pans use side² and width × length. The Cake Pan Converter does this for you and gives a single multiplier.
Do I scale by pan area or volume?
Scale by area when the cake keeps a similar height. Area drives how deep the batter sits and how it bakes. Volume only matters when you also change the pan height substantially — most home swaps keep a comparable depth, so area is the practical choice.
Does cake pan height matter?
Height matters for capacity (how much batter fits) and for very deep versus very shallow pans, but for typical cake pans of similar depth the surface area is the main driver of bake time and texture. Pan height is optional here and not required to get a scale factor.
How should I adjust baking time when changing pan size?
Treat it as directional, not exact. A similar area ratio usually means a similar time. A shallower batter bakes faster, so check earlier; a deeper batter may need a slightly lower temperature or a longer bake. Pan material, batter type and oven calibration all shift the time — always test doneness.