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asked May 6th 2019

Oblong cake servings


I am trying to figure out how big an oblong cake should be to feed 150-180 people. Despite the charts I’ve seen online I’m still struggling to understand as most talk about sheet cake and quarter sheet cake, etc… no idea!

The biggest tin I have is a 9x13inch, I was planning to make it double (2 cakes together – 18x13inch)… my question is will this be enough?

Thank you so much!



I also have a 10x10inch square tin. Will this one work out better to feed 150-180? If I do this double 20x10inch.

Thank you so much.


Hi Cristina

To calculate the surface area of a square or oblong tin, multiply the length by the breadth and divide by the size of the serving portion eg 1″ x 1″ or 2″ x 1″.

If your tin has curved corners, you have to allow for 1″ wastage from both length and breadth. This will make your tin 8 x 12, from this, the yield will be 96 x 1″ squares or 48 x 2″ squares.

If you give 1″ x 1″ squares, it will be necessary to bake 2 cakes, or 4 cakes if you are layering.

If you give 2″ x 1″ squares, it will be necessary to bake 3 cakes, or 6 cakes if you are layering.

I have already answered a similar question and will try and search it out for you and post back.

I was wrong, the question which I thought was similar is about a recipe.


The 10 x 10 would work out better assuming you don’t lose the curved corners. Are you layering or having just one layer?

Please let me know if you need more information.

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