One question I get asked quite regularly is “how much fondant do I need to buy to cover my cake?” So I decided to create a calculator where you enter the size of your cake and it’ll give you an estimate of the amount needed.
Calculating the amount of fondant needed isn’t an exact science as it depends on how thick you want it to be, how good you are at rolling it out to the exact shape you need it and how much excess you’ll have (I usually roll mine out to be about 1cm wider than it needs to be all around, which then allows me to get it nice and smooth and to trim it neatly at the base of the cake).
This calculator gives you an indication of how much you need to buy so you know you’ll have enough, but should prevent you getting carried away and buying far too much.
It assumes your fondant is rolled out to be 4-5mm thick and you have 1cm excess fondant all the way around the cake.
In order to calculate the amount of fondant then you’ll need to measure the height of your cake. This can be a bit tricky if you’ve not made it yet! As a guide, if you’ve made one of my vanilla or chocolate birthday cakes then a 2-layer cake sandwiched with buttercream and a thin layer of buttercream on top will be about 9cm high and a 3-layer cake about 13.5cm high.
Round Cake
Cake Diameter (cm)
Cake Height (cm)
Amount of fondant = 0 grams
Square or Rectangular Cake
Cake Size (cm)
x
Cake Height (cm)
Amount of fondant = 0 grams
Fiona Wheldrick says
HI. I am making my friends wedding cake and she has asked me to cover it in ivory coloured fondant icing to match her wedding dress. Any suggestions as to which is the easiest method or product that I should use?
Charlotte Oates says
I’m sorry, I’ve never researched or used an ivory type colour. You might find that some cake decorating groups on facebook are a good place to start for advice. Good luck with the cake!
Lyn Gibbons says
Thank you so much for the calculator, it is a god send.
Attempting to ice a 4 tier wedding cake for my great niece and just didnt know where to start with quantity.
Interesting that you buy supermarket own brand. I have been thinking l need to buy Renshaw, but maybe l will think again.
Susan morgan says
Hi have you a preferred brand of fondant?
Thanks
Charlotte Oates says
I don’t, I tend to use whatever my local supermarket has. They’re all very similar.
Gloriya says
All your recipes have turned out to be perfect. Love them. Do you have a recipe for a home made fondant??
Charlotte Oates says
I don’t sorry, I always opt for ready-made.
Ian Morgan says
Wonderful calculator, but how thick do you roll the fondant out to?
Charlotte Oates says
I roll mine to be about 4-5mm thick.
Polly Watson says
This is a Great help – thank you very much!
Pam says
Thank you, that will save a lot of guess work.
Sandra Jones says
Thank you for the fondant calculator really helpfull
Claire says
Really helpful article, thanks!
Kate - Gluten Free Alchemist says
There are definitely times when I have needed a fondant calculator! Bookmarked xx
Charlotte Oates says
I hope you fine it useful 🙂