Cooking & Kitchen

Cake Pan Conversion Calculator

A cake pan's area grows with the square of its diameter, so batter scales by area — not by diameter alone.

The result is the factor by which every ingredient amount must be multiplied, so a scale factor of 1.56x means using about one and a half times the original amount of each ingredient.

Formula

Scale factor = (new diameter squared) / (original diameter squared).

How it works

Going from a 20 cm pan to a 25 cm pan is not a 25% increase — area grows with the square, so it is actually about 56% more batter.

When the pan gets much bigger, the layer bakes thinner and faster. When it gets smaller, the layer is deeper and needs longer.

FAQs

What about square pans?
The same idea applies: scale by area. A 20 cm square pan has 400 square cm; a 25 cm square has 625, a factor of 1.56.

Do I need to adjust baking time?
Yes, a little. Larger, thinner layers bake faster; smaller, deeper layers bake slower. Check early either way.

Can I just use two pans instead?
Often yes. Two pans of the original size need no scaling at all — just split the batter evenly.

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