Toolman

28 cm / 11 in round vs 23 × 33 cm / 9 × 13 in

28 cm / 11 in round23 × 33 cm / 9 × 13 in
Size28 cm across23 × 33 cm
Base area615.8 cm²754.8 cm²
Usual depth5 cm5 cm
Holds3.08 L3.77 L

Can you swap them?

Scale the mixture, or accept a flatter cake. 23 × 33 cm / 9 × 13 in has 22.6% more area, so a 28 cm / 11 in round mixture poured straight in sits 82% as deep. It still bakes, and it browns more at the edges for being shallower. Multiplying by 1.23 restores the depth the recipe was written for.

Scaling the recipe

Recipe written forBaked inMultiply byOr leave it and get
28 cm / 11 in round23 × 33 cm / 9 × 13 in1.2382% of the depth
23 × 33 cm / 9 × 13 in28 cm / 11 in round0.82123% of the depth

Multiply every ingredient, including the eggs — round to the nearest half egg and adjust the liquid rather than rounding a whole one up.

Baking time

A mixture 82% as deep is done earlier, not cooler. Leave the temperature alone, start testing at about 82% of the stated time, and let the skewer decide. Why depth sets the time and diameter barely does →

Frequently asked questions

Can I use a 23 × 33 cm / 9 × 13 in instead of a 28 cm / 11 in round?

Yes, with the mixture multiplied by 1.23. 23 × 33 cm / 9 × 13 in has 754.8 cm² of base against 615.8 cm², so an unscaled 28 cm / 11 in round recipe sits 82% as deep and bakes faster.

What is the difference between a 28 cm / 11 in round and a 23 × 33 cm / 9 × 13 in?

28 cm / 11 in round has a base area of 615.8 cm² and 23 × 33 cm / 9 × 13 in has 754.8 cm² — 23 × 33 cm / 9 × 13 in is 22.6% larger. At their usual depths they hold 3.08 L and 3.77 L.

Do I need to change the baking time between a 28 cm / 11 in round and a 23 × 33 cm / 9 × 13 in?

Yes. Moving a 28 cm / 11 in round mixture into 23 × 33 cm / 9 × 13 in makes it 82% as deep, so start checking at about 82% of the stated time. Depth drives baking time far more than tin diameter does.

28 cm / 11 in round in full · 23 × 33 cm / 9 × 13 in in full · All tin comparisons · All baking tin sizes