Toolman

30 cm / 12 in round vs 23 × 33 cm / 9 × 13 in

30 cm / 12 in round23 × 33 cm / 9 × 13 in
Size30 cm across23 × 33 cm
Base area706.9 cm²754.8 cm²
Usual depth5 cm5 cm
Holds3.53 L3.77 L

Can you swap them?

Swap without changing the recipe, but watch the oven. 23 × 33 cm / 9 × 13 in has 6.8% more area, so a mixture written for 30 cm / 12 in round sits about 94% as deep in it and browns sooner.

Scaling the recipe

Recipe written forBaked inMultiply byOr leave it and get
30 cm / 12 in round23 × 33 cm / 9 × 13 in1.0794% of the depth
23 × 33 cm / 9 × 13 in30 cm / 12 in round0.94107% 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 94% as deep is done earlier, not cooler. Leave the temperature alone, start testing at about 94% 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 30 cm / 12 in round?

Yes, with the mixture multiplied by 1.07. 23 × 33 cm / 9 × 13 in has 754.8 cm² of base against 706.9 cm², so an unscaled 30 cm / 12 in round recipe sits 94% as deep and bakes faster.

What is the difference between a 30 cm / 12 in round and a 23 × 33 cm / 9 × 13 in?

30 cm / 12 in round has a base area of 706.9 cm² and 23 × 33 cm / 9 × 13 in has 754.8 cm² — 23 × 33 cm / 9 × 13 in is 6.8% larger. At their usual depths they hold 3.53 L and 3.77 L.

Do I need to change the baking time between a 30 cm / 12 in round and a 23 × 33 cm / 9 × 13 in?

Yes. Moving a 30 cm / 12 in round mixture into 23 × 33 cm / 9 × 13 in makes it 94% as deep, so start checking at about 94% of the stated time. Depth drives baking time far more than tin diameter does.

30 cm / 12 in round in full · 23 × 33 cm / 9 × 13 in in full · All tin comparisons · All baking tin sizes