What does this tool do?
A recipe written for one pan can be baked in another if the batter depth stays similar. Comparing base areas shows how much to scale the batch, whether you are moving from a round tin to a square one or changing the size of the same shape.
The Formula
Round area = π × (diameter ÷ 2)²; square area = side²; rectangle area = width × length; batch multiplier = target area ÷ source areaFrequently Asked Questions
Can I swap a 20 cm round pan for a 20 cm square pan?
Not one-for-one. A 20 cm square pan holds about 27% more batter than a 20 cm round pan, so scale the recipe up or expect a shallower cake.
Does pan depth matter?
Yes. Two pans with the same base area but different depths hold different volumes. Deep tins may need longer at a slightly lower temperature; keep the batter depth similar where possible.