The perfect birthday needs the perfect birthday cake. One that tastes delicious and is just the right size to feed all of your guests.
This vanilla cake calculator will give you the ingredients you need for any size of cake tin as well as the answers to lots of other FAQs to help you get your cake just right.
One post on my blog that’s always popular is my all-in-one vanilla sponge birthday cake. It’s the recipe I use for almost all of my family’s birthday cakes and I absolutely love the idea that people are making and enjoying this on their family birthdays too.
However, it seems that popularity comes with lots of questions and I’m finding similar ones coming up again and again. People have told me that they’ve been scrolling through the comments to see if I’ve answered the questions before but with over 125 comments and counting it cannot be easy to spot the answer you’re looking for in amongst everything else.
To try and help you all out I thought I’d pull together a quick post to answer all of your birthday cake FAQs as best I can and of course if I find new questions popping up in future I’ll add them in here.
Frequently Asked Questions
What ingredients do I need to make this cake in a different size?
What temperature should I bake the cake at?
How long should I bake my cake for
Can I bake two layers in one deep tin?
Can this recipe be used to make cupcakes?
Can this cake be used to make tiers?
How far in advance can you make the cake?
Can you freeze the cake?
Can I use butter instead of margarine?
Can I substitute plain flour for self-raising flour?
What size eggs should I use?
Can I make this cake gluten-free?
How much fondant do I need to cover my cake?
What ingredients do I need to make this cake in a different size?
The most comment question I’m asked is how to calculate the quantities to make the cake in a different size. To help you I’ve built this handy little calculator (I’m quite proud of myself for getting this working actually 🙂 ).
All you need to do is pop your tin size and the number of layers of sponge you want in your cake into the green boxes and it’ll tell you what you need. The first calculator is for a round tin and the second is for a square or rectangular tin.
I’ve also calculated the ingredients needed to coat the cake in a layer of buttercream (with buttercream in between the layers too).
You need to enter the tin size in centimetres, if you only know yours in inches, simply multiply it by 2.5.
NOTE – I’ve not tested the cake in all possible sizes (I don’t have all those different tins for a start) so cannot guarantee success, However, as long as you don’t stray too far away from the original size I expect it should still work well.
Round Cake
- 0 g self-raising flour
- 0 tsp baking powder
- 0 egg(s)
- 0 g soft margarine or butter
- 0 g caster sugar
- 0 drops vanilla extract
- 0 tsp milk
- 0 g butter
- 0 g icing sugar
- 0 tsp vanilla extract Approx.
- 0 tsp milk
Square or Rectangular Cake
- 0 g self-raising flour
- 0 tsp baking powder
- 0 egg(s)
- 0 g soft margarine or butter
- 0 g caster sugar
- 0 drops vanilla extract
- 0 tsp milk
- 0 g butter
- 0 g icing sugar
- 0 tsp vanilla extract Approx.
- 0 tsp milk
What temperature should I bake the cake at?
You can bake this vanilla cake at the same temperature specified in the original recipe regardless of the size of tin you're using.
How long should I bake my cake for?
As long as you split the mixture into sandwich tins the cooking time will be the same as for the original recipe.
Can I bake two layers in one deep tin?
Yes you can. However it will take longer to bake.
If you put the mixture for two layers into now deep tin you'll need to bake the cake for 45-50 minutes.
Can this recipe be used to make cupcakes?
Yes, you can find the recipe to make this cake as cupcakes here.
Can this cake be used to make tiers?
My parties are all pretty small so I've never needed a cake big enough to justify tiers. It is quite a soft, light sponge and so I would expect it to be fine for 2 tiers but personally I wouldn't risk 3.
If you are planning on making two tiers remember to include some sort of support in the lower layer (strong straws or dowelling cut to the height of the cake, and also put the top tier onto a thin cake board the same size as the cake (this adds additional support and also stops the moisture from the sponge ruining the fondant on the bottom layer).
How far in advance can you make the cake?
I usually bake my cakes on a Thursday and decorate them on a Friday for a Saturday party. We only have small parties so there's usually some leftovers which have always lasted for a few days after the party.
Make sure you store it in an airtight container to keep it fresh and if the weather is particularly warm I'd suggest keeping it in the fridge.
Can you freeze the cake?
Yes, you can freeze the undecorated sponge. Simply wrap it in clingfilm or an airtight bag and pop it into the freezer. When you want to use it remove it from the freezer and then make sure it's fully defrosted before decorating.
Can I use butter instead of margarine?
Yes, just make sure you take the butter out of the fridge a little before you want to start baking to allow it to soften.
Can I substitute plain flour for self-raising flour?
I've only ever used self-raising (as I've always got it in the cupboard). Nigella suggests you can substitute plain flour by simply adding an extra 2 tsp of baking powder for each 150g of flour used (so for my original recipe you'd need an additional 3 tsp of baking powder).
What size eggs should I use?
I use whatever I have in the fridge! Most of the time that'll be medium eggs but it works just as well using large.
Can I make this cake gluten-free?
You should be fine to substitute the self-raising flour for a gluten-free self-raising flour. Also, double check that the brand of baking powder you're using doesn't contain gluten (some do, some don't).
How much fondant do I need to cover my cake
If you'd like an idea of how much fondant you need to cover your cake then head on over to my fondant calculator where it'll tell you for any size of round, square or rectangular cake.
FREE GRAMS TO CUPS CONVERSION CHARTS
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This post was originally published on 17th May 2016 and updated with an improved calculator and more FAQs on 11th July 2018.
Barbara Williams says
I want to make a sponge for a 70th birthday, I’ve got a 20cm square tin, should I make 2 tins then sandwich them together
Charlotte Oates says
That’s what I would recommend doing.
Sue says
Hi how long will this cake last when made and iced
Charlotte Oates says
Mine are always fine for about 4 days.
Helen says
Hi Charlotte, I’m so excited to make this cake! What ingredients would you use to make a 23cm round cake into a lemon version please?
Charlotte Oates says
You can find the ingredients for a 23cm vanilla cake using my calculator. To adapt it to be a lemon cake, simply ditch the vanilla extract and replace it with lemon zest. Use the finely grated zest of half a lemon for each egg in the mixture (so for a 2-layer 23 cm cake you’d need the zest of 2.5 lemons.
trisha says
Hi I followed the recipe for a 20cm x 20cm square tin and baked for 45 minutes as stated in the information for baking in a deep tin. The middle was all sunken. What went wrong. We did not open the oven.
Charlotte Oates says
Was it cooked when you checked after 45 minutes?
Neelam says
Hi Charlotte,
I’ve used the calculator for a 25cmx25cm square cake and 25cm round cake – deep tins for a 2 layer cake with each.
Both rose beautifully then sunk in the middle. I tried twice thinking it was something I was doing wrong but it simply doesn’t work! Help! Yet I did the original version and split it between 2 smaller tins and it was perfect!
I made sure I weighed and sieved everything, didn’t overwork the batter and I always put my cakes in at 150 in a fan oven. I left them for an hour an 10 but the same result.
Any ideas?
Charlotte Oates says
I’m not too sure why that happened sorry. I usually bake the cake in 2 sandwich tins, but I know a lot of people bake it successfully in one deeper tin.
Jacqueline Quinn says
Fantastic calculator!
Thank you.
tracey says
hi charlotte
Is it ok to use smalll mixed etc eggs for vanilla sponge . and what butter is best for sponge as my cake was a bit greasy.
could i use this sponge for a teir naked wedding cake or would you suggest maybe a maderia if so do you have a recipe as i cant find yours .
thankyou
Charlotte Oates says
You can use smaller eggs, but your cake will not rise as much and will have a crumblier texture (so not as strong if you’re making a tiered cake). Personally if I had smaller eggs I’d weigh the eggs (after cracking) so that you have a total weight of egg of 50g x the number of eggs in the recipe (so for the original 20cm 2-layer round cake your egg would weight 200g).
This cake definitely works for 2 tiers (I’ve seen a lot of photo evidence of that) and should work for 3. I personally wouldn’t go higher than that. If you want to make tiers ensure you add some dowels/straws for extra support.
I use Stork for mine. Make sure it’s mixed in thoroughly. If there are any little lumps of butter or marg that aren’t mixed in they tend to melt rather than baking into the sponge leaving the bottom a little greasy. Cakes can also seem a little greasy if there’s too much butter. If you’ve used smaller eggs then the ratio of butter to other ingredients will be too high which may also explain the problem.
tracey says
Thank you charlotte
How long should my 10″ x 4cm depth round take to cook as mine took 50-55 mins which I thought was long as its a single sponge . I cooked it in the middle gas mark 3 . If I cooked a 10″x4″depth round 2 layer how long would you say to cook it for . thanks
Charlotte Oates says
I would usually expect a two-layers in one tin cake to take about 45-50 minutes. It can vary depending on the oven so whilst yours was a little longer its not hugely outside what I would have expected.
tracey says
Hi charlotte making a 3 layer 10″ round sponge cake do i have to cook separate and what is the depth of the tins if so .
Charlotte Oates says
I would cook them separately in 3 sandwich tins (c. 3cm depth although they do vary).
Maggie Speirs says
Hi I have just made your recipe for a tray 26cm x 36cm to make two shallower cakes for my grandson’s large birthday cake – the calculator worked just as promised and the two cakes – to be sandwiched together – were excellent
Liji says
Hi Charlotte
I am Liji I am planning to bake a 9 inch 23 cm cake and 7?inch cake for my daughter 3 birthday I would like to get the quantities that required to make these two inch cakes. Also I am using cake gel do can you please advise me how much cake gel is needed for this birthday cakes. Thanks
Charlotte Oates says
Hi Liji, is there any reason you’d like to add cake gel to the recipe? it’s not something I’ve used before so can’t answer your question about that – sorry, If it’s something you’re definitely keen on using then I’d suggest looking for an alternative recipe online that includes it in the ingredients list.
Steph says
Hi Emma, I’d love to bake this cake for my daughter’s 1st birthday in a large rectangle shape (35.5 x 25.5cm) with two layers so will be baking it as two separate cakes. How long would you recommend cooking each layer? Would I do them separately or put them in the oven at the same time of two separate shelves? Also is this recipe compatible with a vanilla syrup glazed over for flavour and moisture?
Thanks in advance! Steph
Charlotte Oates says
Hi Steph, If you’re using the layers with the ingredients given in the calculator then they should be cooked in 30-35 minutes as per the original recipe (the cooking time varies far more by cake depth than the tin width). Personally with a cake that size I’d cook the two layers one after the other. You can cook them at the same time on different shelves but you may find the one at the bottom doesn’t cook as well. I’ve not tried it with a syrup glaze but it should work. However it is quite a moist cake to start with so may not be needed.
Maggie Speirs says
I made 2 this size today and it took 40 minutes at 150 in a fan oven for each cake.
Karen says
Hi Charlotte,
I was wondering if you could please help me
I can’t open or even see your calculators on my phone for some reason…
I am making a unicorn cake for my wee girls 7th birthday party on Saturday
I have a 12″x12″ cake board & I’ve drawn out my design. I have a tin which is roughly 25x35x6.5cm. 24 kids are invited to the party {I’m not sure what the actual number attending will be but I do love birthday cake so the more cake the better } & I’m wondering whether I’m best doing 2 layers of sponge {so baking 2 cakes & layering with a jam & butter cream filling} rather than 1 thicker layer {+/- cutting it across the middle & filling ~ I’m undecided} ~ I’m thinking 2 cakes….
Would you be able to give me advice based on your experience & quantities if you don’t mind please?
Thank you so much
Karen x ♥
P.S. It was so nice to come across a British page with measurements I understand
Charlotte Oates says
Hi Karen, sorry if I’m too late I’ve only just seen this.
Personally I would bake two sponges as splitting a cake that size and shape evenly would be tricky.
The ingredients you’d need to make two layers of a cake that size are…
620g SR flour
620g margarine
620g caster sugar
11 eggs
5.5 tsp baking powder
1/2 tsp vanilla extract
5.5 tsp milk
Mary Pictor says
I’ve just come across this site – great to have English meaures etc. I did find that I needed to download the calculator into Excel in order to enter new amounts as it is a protected page. Thank you for your help.
Charlotte Oates says
That’s strange. The embedded sheet is protected to stop anyone accidentally typing in any cells that make calculations leading to incorrect measurements. The cells where the tin size and number of layers should be be protected. If you try again in future and get the same error it would be great if you could screenshot it for me so I can take a look.
I’m planning to change the calculator soon so it no longer uses an excel spreadsheet which should hopefully fix the problem.
Ranjana Surplis says
Hi Charlotte,
I am going to give your recipe a try for my daughter’s 3rd birthday. Our cake will be 12inches x 8 inches rectangular. I want to a single tall cake (about 5-6cms). Is it possible to use measurements on your calculator for 2 layers but bake it as a single layer cake ? ie not slice it from the center or bake as 2 sandwich layer cakes, but instead pour the entire batter into the baking tray and bake it in one go ?
Also I wish to halve the quantity of sugar as buttercream is loaded with sugar. 🙂 do you think that will change the texture of the cake ?
And lastly can you suggest how do I get a strawberry flavored cake ?
You are brilliant with the calculator on your website. Well done your clever girl 🙂
Charlotte Oates says
You should be find to cook two layers in one deep tin. As it’s deeper it’ll take 45-50 minutes to cook. You should be fine to reduce the ratio of sugar to butter in the buttercream (I do this with some of my different flavours to make them a little less sweet). It should still work fine.
I haven’t yet perfected a strawberry cake using real strawberries. The approach I’d take is to add some strawberry flavouring into the vanilla cake mixture (I’d suggest about 1 tsp).
Maggie Speirs says
What about dried strawberry powder – I have blackcurrant by Arctic Power Berries
Charlotte Oates says
I haven’t tried it so couldn’t say for sure. Sorry.
Raheemah Gondal says
Hi Charlotte, I have got a 10inchx10inch square tin which is 3inches deep and not sure the quantities of the ingredients. I am wanting to make one single cake but has two layers sandwiched between jam and cream and will be covering it with fondant. Please would you be able to help me with the quantities?
Charlotte Oates says
If you put 25cm x 25cm into the square/rectangular calculator it’ll tell you the ingredients you need for the cake. For as 3″ deep tin put 2 layers into the calculator and then cook all of the mixture in the one tin As the tin is deeper you’ll need to cook it for 45-50 minutes. The recipe uses medium eggs but will work with large if that’s all you have. If you use large you’ll find the sponge is a little firmer and slightly less moist that using medium.
Jenny says
Hi Charlotte
I am planning my daughters birthday cake which is a layer cake 9 inch with 4 layers. On your calculator you suggest 10 eggs, is that large or medium? Also 15 drops of vanilla extract, how many tsp is that and how long should I cook it for? Also the same for the icing how many tsp vanilla extract?
I made your birthday cake recipe for a trial and it was the best cake I’ve ever made absolutely delicious so glad I found your recipe thank you!
Charlotte Oates says
Medium eggs. 15 drops is about 1/4 tsp. Are you cooking the 4 layers in 4 sandwich tins or in 2 deeper tins and then cutting in half? If you’re using sandwich tins then they cook for the same time as stated in the recipe. If you’re using deeper tins then they’ll take 45-50 minutes. Fir the icing you’ll need 1 1/4 tsp of vanilla extract.
Jenny says
Thank you for your reply Charlotte that’s very helpful! I brought a layer cake tin set which are four separate sandwich tins which are 9 inches by about 1 inches deep so shall I cook it for 30/35 mins as stated in your original recipe? Also with the buttercream icing as I’ve put a four layer cake in your calculator I take it that’ll be enough to sandwich the layers together and have enough to go on the outside of the cake to stick fondant the to?
Charlotte Oates says
Yes, put 4 layers into the calculator to get the ingredients and cook each layer for 30-35 minutes. If you’re cooking them all at the same time you may find they need a little longer as the oven is fuller (especially the ones underneath).
The calculator is designed to calculate the buttercream to fill each layer and to cover the top and sides of the cake with a thin layer.
Susan Callinswood says
Hi Charlotte, I wonder if you could please help me out as now im panicking!!! I have bought one square 23cm cake tine(no loose bottom) oh and the depth is 7cm(so just under 3 inches, I want to make a classic sponge cake with buttercream in the middle and then want to buttercream it all over before I use fondant icing on top. I have looked at your calculater but to be honest I am still unsure of the exact ingredients that I need? I also need to know the ingredients for the butter cream, and what tempreture I need for a fan assisted oven? I am not sure, but I think the cooking time is around 45/50 mins.I would also like to ask you the best way to cut it across once cooled, so I can apply the buttercream in between the two layers. this will be a 50th birthday cake for my husband, and as I am an ameture when it comes to baking large cakes, I really need some accurate and good advice. I will need to start this cake in around 5 days!!! Thank you.
Charlotte Oates says
If you put 23 x 23 into the calculator with 2 layers that will give you the ingredients you need for both the cake and the buttercream. You should cook it at the same temperature as suggested in the original recipe (140C for a fan oven) and you’re right that it should take 45-50 minutes to cook. `I always make my cakes in sandwich tins so don’t have to cut them in half. However, I would recommend making the cake the day before (or at leave a few hours before) you attempt to cut it in half. The cake is soft when it comes out of the oven so leaving it for a few hours (in an airtight container) will make it easier to slice. Use a bread knife to cut the cake, alternatively you could order something like this https://www.amazon.co.uk/KitchenCraft-Sweetly-Does-Cake-Cutting/dp/B000YJD81K/ref=sr_1_14?ie=UTF8&qid=1517067055&sr=8-14&keywords=cake+knife which allows you to set the height you’re trying to carve the cake to so it doesn’t go wonky. If you don’t fancy buying the cake wire another hack I saw on Facebook (I have’t tried it but I’m sure it would work) it to measure the same distance up the side of the cake where you want to slice and stick cocktail sticks halfway in at regular intervals. These can then be used as a guide for the knife to keep things straight.
Susan Callinswood says
Thank you so much Charlotte, you are a life saver!! you have been so helpful and informative. I will keep you informed of the outcome 🙂
Petal says
Hi Charlotte I tried this recipe today for a 10inch and I divided the mixture between 2 tins was amazing!! I really need some helo/advice. I am wanting to bake a 12 inch,10inch,8inch and 6 inch cake when I put measurments in your calculated the quantities given are they for 2 layers? or can all the mixture be put in one tin and cooked? If it can then how long would it need to be in the oven for and how long for and what temp in fan assisted oven?? Thank you in advance hope u can help.x
Charlotte Oates says
The default number of layers in the calculator is 2 but you can change this to any number you want. You can put the mixture for two layers into one deep tin. If you do that then it’ll take 45-50 minutes to cook at the same oven temperature as given in the original recipe.
donna says
hi iv got a 11 cm 7 square tin howm much ingrdients do i nee to make a lemon sponge birthday cake with fondant icing pls .for my hubby whos birthday is thursday 21 june
Charlotte Oates says
Is that a 7″ square tin?
Assuming it is, you’ll need…
170g self-raising flour
170g margarine/butter
170g caster sugar
3 eggs
1.5 tsp baking powder
A few drops of vanilla extract
1.5 tsp milk
If you’re baking the cake in one deep tin then it’ll take 45-50 minutes to cook.
I usually coat my cake with buttercream (in the middle and around the outside) before covering with fondant. For this you’ll need…
205g butter
410g icing sugar
0.5 tsp vanilla extract
A little milk
To cover the cake with fondant icing once you’re done you’ll need c. 930g of fondant icing. This will allow you to roll the fondant to be 4-5mm thick and a little bigger than the cake so that it’s easier to get it neat.
Gillian Mac Nab says
Hi Charlotte
This cake came out beautifully but it’s a bit sweet for my taste. Could I halve the sugar and have the same result.
Many thanks
Gillian
Charlotte Oates says
I’ve not tried it but it should work fine.
LINDSEY says
After making my son in law’s B’day cake & it being a great success, i will only ever use this sponge recipe now. Last month I made 8 sponge cakes to make my Dad’s ‘huge’ number ’80’ birthday cake,the whole family absolutely loved it & demolished in 2 days, they thought it had been made by our local artisan bakery. I’m now baking sponges once again, breaking them up & leaving them overnight to go ‘stale’ so i can make my Brother’s birthday cake (a russian Tipsy cake). I’ll let you know how it works out. Thanks to your recipe Charlotte I am now the ‘go to’ for b’day cakes in the family. 🙂
Charlotte Oates says
8 cakes, that’s impressive! I’m glad everyone enjoyed it. I’ve not tried a tipsy cake before, I’ve just been Googling it and it sounds delicious. I hope it works well for you x