20 cm / 8 in square vs 23 cm / 9 in square
| 20 cm / 8 in square | 23 cm / 9 in square | |
|---|---|---|
| Size | 20 × 20 cm | 23 × 23 cm |
| Base area | 400 cm² | 529 cm² |
| Usual depth | 5 cm | 5 cm |
| Holds | 2 L | 2.65 L |
Can you swap them?
Scale the mixture, or accept a flatter cake. 23 cm / 9 in square has 32.3% more area, so a 20 cm / 8 in square mixture poured straight in sits 76% as deep. It still bakes, and it browns more at the edges for being shallower. Multiplying by 1.32 restores the depth the recipe was written for.
Scaling the recipe
| Recipe written for | Baked in | Multiply by | Or leave it and get |
|---|---|---|---|
| 20 cm / 8 in square | 23 cm / 9 in square | 1.32 | 76% of the depth |
| 23 cm / 9 in square | 20 cm / 8 in square | 0.76 | 132% 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 76% as deep is done earlier, not cooler. Leave the temperature alone, start testing at about 76% 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 cm / 9 in square instead of a 20 cm / 8 in square?
Yes, with the mixture multiplied by 1.32. 23 cm / 9 in square has 529 cm² of base against 400 cm², so an unscaled 20 cm / 8 in square recipe sits 76% as deep and bakes faster.
What is the difference between a 20 cm / 8 in square and a 23 cm / 9 in square?
20 cm / 8 in square has a base area of 400 cm² and 23 cm / 9 in square has 529 cm² — 23 cm / 9 in square is 32.3% larger. At their usual depths they hold 2 L and 2.65 L.
Do I need to change the baking time between a 20 cm / 8 in square and a 23 cm / 9 in square?
Yes. Moving a 20 cm / 8 in square mixture into 23 cm / 9 in square makes it 76% as deep, so start checking at about 76% of the stated time. Depth drives baking time far more than tin diameter does.
20 cm / 8 in square in full · 23 cm / 9 in square in full · All tin comparisons · All baking tin sizes