Whenever the terms square and round cake tins enter a conversation, you can be assured that a question related to either of the following with crop up:

Question 1. Volumes

For a given size of tin, which one will hold a larger volume?

Question 2. Recipes

How do I adjust a recipe from a square to round cake tin or visa versa?

### Easy Conversions Guide For Square and Round Cake Tins

An easily remembered *conversions guide for square and round cake tins* would be the following:

**Answer 1.
A round cake tin will hold approximately 25% or a 1/4 less than a square tin**

and

**Answer 2.**

** Use a round cake tin that is one size larger than a square tin for a given recipe**

Therefore, we can make a simple quick comparison chart (in inches) for adjusting a recipe from a square to round cake tin or visa versa.

5″ | 4″ |

6″ | 5″ |

7″ | 6″ |

8″ | 7″ |

9″ | 8″ |

10″ | 9″ |

11″ | 10″ |

12″ | 11″ |

13″ | 12″ |

14″ | 13″ |

15″ | 14″ |

16″ | 15″ |

For practical usage that covers what you need to know.

……however, for anyone interested in the mathematics, the following might be of interest!

### Advanced Conversions Guide For Square and Round Cake Tins

A1.VolumesPlease note: For comparison, we willuse a depth of 4 inches |
||

Formula for Volume | 3.14r^{2}d |
L^{2}d |

Explanation | 3.14 is an approximation for pi r= radius is half of the diameter r ^{2}= r x rd= depth (4 inches in the example) |
Because it is a square, the length (L) is the same as the width L ^{2}= L x Ld= depth (4 inches in the example) |

Example:6 inch tin |
If we use the formula above then6 inch tin has a radius (r) of 33.14r ^{2}d3.14 x 3 ^{2} x 4=3.14 x 9 x 4= 113.04 |
Using the formula above then6 inch tin has a length (L) of 6L ^{2}d6 ^{2} x 4 =36 x 4 = 144 |

Therefore, comparing the round cake tin to the square cake tin, we have:

113.04 compared to 144 which can be shown as

113.04 : 144 or

1: 144 ÷ 113.04

which equals approximately 1: 1.27

Thus, the square cake tin has a volume about 27% larger (which we simplified as approximately 25%) than the round cake tin for the ‘same’ size of tin and depth.

A2.Recipes |
||

Explanation | 6″ round cake tin means the tin’s diameter is 6 Therefore it has a radius (r) of 3 Area of circle= 3.14r ^{2}3.14 (3 ^{2}) =3.14 (3 x 3)= 3.14 x 9= 28.26 square inches We now to need find the length (L) for the square cake tin i.e. the ‘size’ of the square cake tin Area of square= L ^{2}and we know the area to be 28.26 from above Therefore, L ^{2}= 28.26We can find L by obtaining the square root of 28.26 L is therefore approximately 5.32 So, if we round 5.32 to the nearest inch, we arrive at 5 |
5″ square cake tin means the length (L) is 5 Area of square = L ^{2}5 x 5 = 25 square inches We now need to find the diameter of the round cake tin i.e. the ‘size’ of the round cake tin Area of circle = 3.14 r ^{2 }and we know the area to be 25 from above Therefore, if we re-arrange the above formula we get r ^{2 }= Area of circle ÷ 3.14r ^{2 }= 25 ÷ 3.14r ^{2}= 7.96We can find r by obtaining the square root of 7.96 r is therefore approximately 2.82 Finally, the diameter of the round tin is 2 x r = 2 x 2.82 = 5.64 So, if we round 5.64 to the nearest inch, we arrive at 6 |

Summary | 6″ round cake tin is equivalent to a 5″ square cake tin |
5″ square cake tin is equivalent to a 6″ round cake tin |

Therefore, the key points you should take from this **conversions guide for square and round cake tins** are:

**A round cake tin will hold approximately 25% or a 1/4 less than a square tin**

**and**

** Use a round cake tin that is one size larger than a square tin for a given recipe**

Other articles of interest:

Care of Cake Tins