Convert between pan sizes by area and scale the recipe accordingly.
Pans scale by area rather than by diameter, so a 23 cm round pan holds about 32 per cent more than a 20 cm one despite being only 15 per cent wider. Depth changes inversely with area if the recipe is unchanged. Batter depth determines baking time and texture, so an unscaled recipe in a larger pan bakes faster and comes out dry rather than merely thinner.
Pan Size
Scale factor = target pan area ÷ original pan area
Scale factor = target pan area ÷ original pan area Pans scale by area rather than by diameter, so a 23 cm round pan holds about 32 per cent more than a 20 cm one despite being only 15 per cent wider. Depth changes inversely with area if the recipe is unchanged.
Batter depth determines baking time and texture, so an unscaled recipe in a larger pan bakes faster and comes out dry rather than merely thinner.
This calculator takes 6 inputs: Original pan shape, Original diameter or length, Original width, rectangles only, Target pan shape, Target diameter or length, Target width, rectangles only. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.