How Much Buttercream Do I Need?
The age-old question…how much buttercream do I need?? For a batch of cupcakes? A 6-inch layer cake? For a wedding cake?!
This post shares everything you need to know to make the perfect amount of frosting for any baking project. It’s basically the frosting version of my cake batter calculator.
The amount of frosting you need varies based on the following factors:
- Size of cake layers
- Shape of cake layers
- Number of cake layers
- Decoration style (semi-naked, smooth, buttercream rosettes, large swirls on top, etc.)
With the help of my buttercream formula and chart below, you’ll be able to figure it out in a snap!
Does It Matter What Type of Buttercream I’m Using?
This guide can be used for pretty much any type of frosting. Whether you’re using American, Swiss, Italian, Russian, or even German, a cup of frosting is a cup of frosting.
My only note on this is that I find I sometimes need a tiny bit more American buttercream to make a perfectly smooth cake.
If I’m using a meringue-based frosting, it usually is a bit easier to smooth, and I can use slightly less on the sides of the cake.
How Does This Buttercream Calculator Work?
Creating this chart meant thinking through what we’re trying to calculate.
To know how much frosting we’ll need, we need to use the formula of a cylinder, the formula of a circle, and then back out how many cubic inches are in a cup to get to our answer.
With that in mind, the formula I used is:
Cups Needed = ((area of a circle x thickness of the layer of frosting x number of layers) + (surface area of a cylinder minus top and bottom)) / by cubic inches per cup
Or in terms of numbers for a 6-inch, 2-layer cake, this meant:
Cups needed =((pi x r in2 x .33 in) + (2 x pi x r in x h in x .25 in))/14.4 in3
I had to make some assumptions in this formula, including that the outer coat of frosting will be about 1/4 inch thick and that the frosting layers inside the cake will be about 1/3 inch thick.
This is based on how I actually decorate my cakes! I love thick layers of frosting inside, just like in my death by chocolate cake shown above.
However, if you use a lot less frosting between your cake layers, or if you want to make a design that requires a lot of extra buttercream (like buttercream rosettes), these numbers might need to be adjusted.
If you aren’t a big fan of math, don’t worry! I’ve used this formula to create a chart below that’s super easy to use. It’ll instantly tell you how much buttercream you need 🙂
Step 1: How Big is the Cake You’re Making?
The size, shape, and number of cake layers will impact how much frosting you need.
In general, I find that one batch or about 6 cups of frosting is the perfect amount for a 7-inch or 8-inch layer cake that’s decorated with buttercream swirls on top.
I usually have a tiny bit left over, but it’s just about right. This makes sense based on my calculations below!
Step 2: Use My Buttercream Calculator to Figure Out How Much Frosting You Need
Based on the size of your cake, use the charts below to figure out how much frosting you need. This is just to fill, crumb coat, and cover a layer cake.
Add an additional 1-2 cups of frosting to the numbers below if you want to pipe large buttercream swirls on top of the cake.
Or if you want to make a frosting-intensive design like covering a cake in buttercream rosettes, add an additional 2-3 cups of frosting for a cake ranging from 6-8 inches. It sounds insane, but those designs require so much extra frosting!
Step 3: How Many Cups of Buttercream are in One Batch of Buttercream?
Now you just need to figure out how many cups of frosting one batch makes.
My American and Swiss Meringue buttercream recipes both make about 6 cups of frosting.
However, it can vary based on the recipe you’re using.
Most recipe cards list the yield at the top of the recipe card or share it in the notes section at the bottom of the recipe card.
Now that you know how many cups of frosting you need, you can work back to how many batches of frosting you’ll need to make.
And just like that, you’re ready to make the perfect amount of frosting!!
I’d love to hear if you found this post helpful, or if you end up using it! Tag me @chelsweets and #chelsweets on social media.
You can also download the charts above here!
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Amazing! The numbers behind it, are a hug to my inner nerd! Thank you!
Finally!!! Someone decides to help us novices. Thanks Chels?
These charts are amazing. A million thanks!!! ??????
Hi
I am a huge fan of your blog. It is my go to place to find answers to my baking dilemmas. I am attempting a 3 tiered wedding cake and will make your vanilla cake and buttercream recipe. It is going to be a 6″, 9″ and 12″ round wedding cake. From your handy calculators I figured I would need 4 batches of the batter and 26 cups of buttercream. It is going to be decorated with fresh white roses.
I just started baking to generate some income and struggle with how much to charge , can you please give me a ballpark figure of what I can charge for this cake.
Thanks in advance
Hello Chelsea,
I recently discovered your website, and your YouTube channel. I appreciate the charts they are extreamly useful. I was also hoping that you could perhaps create a similar type of chart for the amount of filling required for the various size cakes.
Thanks You,
Chanel
Thank you, so helpful
I love your recipes and tutorials! I am going to be making my daughter’s wedding cake, a first for me, and I was planning on making a 4 tier (10, 8,6 & 4 inch) cake. I saw you do this on you “how to make a wedding cake” tutorial but have a question regarding the centre dowel. I see you put one in which went part way up the 6 inch layer, then did you put another dowel in for the top that went down to the middle of the 6 inch cake? My dowel is not long enough to go all the way up to the top layer and not sure if I need to find a longer one or if I can use 2.
Thank you so much, I always seem to have either huge amounts of butter cream left or find myself making a rush batch because I’ve run out.
Hi Nas,
I used to run into that all the time too!! So happy to hear you find this post helpful 🙂
I just stumbled upon your website and it is so informative – thank you for posting step by step, recipes and calculations. They are super helpful for beginners like myself. I am attempting to bake my daughter’s 1st birthday cake (eggless/nut free w/ buttercream frosting)
My question is how do i calculate the amount of ingredients for the buttercream? According to your above post, for an 8 inch 2 layer cake i will need 4 cups of buttercream. But I also would like some left over buttercream to try and make some design rosettes on top of cake.
thanks.
Hi Krissy,
Thank you so much for sharing, you’re too sweet! To figure out how many ingredients you need, you just need to know how much frosting whatever recipe you plan to use makes. For example, one batch of my American buttercream recipe (https://chelsweets.com/the-best-american-buttercream-recipe/) makes about 6 cups of frosting. With that in mind, one batch would be perfect for your cake, because you would have enough to frost the cake and have 2 cups leftover for decorating the top of the cake.
Most recipes share how much they make either at the top or bottom of the recipe card. Hope that helps, happy baking!
could you clarify where you get this .33 value in this equation? =((pi x r in2 x .33 in x 2
For sure! The .33 value assumes that the layer of frosting between the cake layers will be about 1/3 inch thick. My cake layers are usually about 1-inch tall, and I find I like that frosting to cake ratio 🙂 Hope that helps, happy baking!
How many cups of buttercream would I need for a full sheet cake (18×24)?
Hi Kisha,
It depends on how thick of a layer of frosting you want, but in general 6 cups of frosting should be enough to cover the top of the cake, and I’d recommend 9 cups if you want to cover the sides of the cake. Hope that helps, happy baking!
Thankyou so much for this!! Makes things easier! ???
@Sarah S.,sorry meant to put only !!!!! Exclamation 🙂
Hello!
Thank you for this
I am not sure how to calculate how much buttercream to make if I have to decorate about 80 cupcakes with simple rosettes .
Can you help me out?
Thank you
Hi Ghina,
It can vary a bit based on how big of a rosette you pipe, but I’d estimate that you’d need about 2 cups per dozen, so probably about 12-13 cups for 80 cupcakes. Hope that helps, happy baking!
Could you please make a chart for sheet cakes or would I just do one and a half batches of a square?
Hi Ashley,
I do need to make another chart for sheet cakes! I’m adding it to my to-do list, stay tuned!
Hi Chelsea,
Thank you so much for the formula. I was trying to compute how much filling vs. frosting as I am going to fill with a different buttercream. I used the formulas you gave (Thanks for this) then spent several minutes trying to figure out why my numbers were lower than yours
I finally realized that you are multiplying by the number of layers for the filling calculation as opposed to (number of layers -1) which is effectively the number of filling layers.
I will use your formula to be on the safe side and since it is tried and true.
When I use the number of cake layers instead of filling layers, my frosting + filling cups match yours.
I really appreciate your thorough explanation.
Hi Sylvie,
Amazing!! I’m so happy to hear you’re putting my formula to good use 🙂 Thank you for sharing!!
Hi Chelsea,
I am using your chart to determine how much frosting I need for my daughter’s wedding cake. I wonder how much I should reduce, in cups, for a semi-naked cake?
Thank you for your input! I love your website and tutorial videos!
Hi Kathy,
You’d need about half the frosting that the chart recommends for a semi naked cake. Hope that helps, happy baking!
I’m making a 7” base Barbie dress cake (for the first time) with a 2 layer 10” cake under it. I want to completely cover both with rosettes. Dress is one color, base another color.
How many batches of your vanilla buttercream will I need?
Hi Denise,
That is a unique shape / size combination! I’m assuming you’ll also need buttercream to fill and crumb coat those cake layers? With that in mind, I’d guess you’d need at least 3 batches, if not 4!
I love the volume of frosting you use between layers, but I can never seem to get it right or consistent. Do you know approximately how much you you put between layers on an 8″ cake?
Hi Dorothy,
I am always very generous and use a few big spatula scoops! My method isn’t very scientific, but I know some bakers who use a big cookie scoop and add a set number of scoops to keep the frosting between the layers perfectly consistent. I’d recommend giving that method a try! Hope that helps, happy baking!
Great, thanks for the amounts, now where is your recipe for buttercream frosting.. Novice baker, need a simple recipe with enough to make a ribbon around the top. THankyou.
Hi Dona,
Here’s the link to my go-to American buttercream recipe: https://chelsweets.com/the-best-american-buttercream-recipe/
However, one batch makes 6 cups, which sounds like a lot more than you’d need! You can make a half or quarter batch if needed!
Hello there,
Your guide on the amount of buttercream/frosting when making cakes is well detailed. But I got a question to ask and how much buttercream I need when it only requires one layer, especially when I’m looking to make one that is dairy-free from scratch?
Hi! It depends on the size of your cake layer! I’d use the chart in this post to find the size of cake you want to make, and then halve the amount listed for a cake that size with 2 layers.
In regards to making a dairy free frosting from scratch, I have a great recipe for that!! Here’s the link: https://chelsweets.com/vegan-buttercream/
Hope that helps, happy baking!
How do i convert this into grams?
Hi Anastasia,
It can’t really be converted to grams because different types of buttercream weigh different amounts :/ Unless you weigh out 1 cup of the frosting you plan to use and then convert it that way! It can be converted to ounces though if that helps?? So sorry!
Hi I’m looking forward to making your buttercream recipe. I will be making 72 cupcakes for my daughter’s wedding with tall swirls on top and wanted to know if you could tell me how many cups of buttercream I would need for that?
Hi Delana,
I’d say you’d probably need about 12 cups of frosting! But it can vary a bit based on how tall the swirls are. Hope that helps, happy baking!
Is there any where that you have calculations for the amount of frosting needed to crumb coat & frost a 1/2 sheetcake?
Hi Suzanne,
Sadly I haven’t done the calculations for that yet! I did make a sheet cake guide, but it just covers the amount of servings and the amount of batter you need for different sized sheet cakes. I’m so sorry! That will have to be my next math project!!
Hi good day.
I love your use of mathematics in real life scenarios!! Makes me appreciate learning all those formulae in school.
Can you clarify what the height (h) of the cake would be in the part of the formula (2 x pi x r in x h in x .25 in) please??
Also, where in the formula would I multiply by the number of layers? I didn’t see it in the formula above
Could you use an example, say 10 inch 3 layer round cake, to show me please??
Thank you.
Hi Arianna,
Totally agree!! Love putting mathematics to good use 🙂 The height of the cake is roughly how tall you think the cake will end up being. This can vary based on the recipe you use, but my cake layers are usually about 1 inch tall, and i make the frosting layer about .25 inches thick, so a 4 layer cake would be about 5 inches tall. Hope that example helps!
To adjust the amount of layers, you’d change the 2 in this equation to be however many cake layers you have: (2 x pi x r in x h in x .25 in))
For example, if you had 4 cake layers, the equation would look like this: (4 x pi x r in x h in x .25 in))
A 10 inch, 3 layer cake would be: ((3.14 x 5 in2 x .33 in) + (3 x 3.14 x 5 in x h in x .25 in)). You’d have to add in the height you think the cake will be. Hope that helps, happy baking!
How much buttercream should I use for an 8 inch hemispherical cake? I would need the buttercream for the inside layer of cake and to make crumb coat
Hi Morgan,
Do you mean just to coat the outside of the cake? The formula for surface area of a hemisphere is 3?r2, so you’d need the multiple the thickness of the layer of frosting in inches x 3?r2. If you wanted it to be 1/4 inch thick, it would be 0.25 x 3 x 3.14 x 16 = 37/14.4cubic inches per cup = 2.7 cups of frosting. Feel free to adjust the thickness as needed. Hope that helps, happy baking!
for some reason the pi sign is showing up as a question mark, apologies!
Can 1kg of icing and 1and half of butter be okay to make a butter cream icing for a 7 inches love cake
@Mickey launch, I don’t understand pls tell me is it okay to use 1kg and 1and a half in butter cream icing for love cake
Hi Mickey,
It’s better to measure by volume for this, because different types of frosting weigh different amounts! What type of frosting are you using? That sounds like it should definitely be enough for a 7-inch layer cake though!
This is soooo helpful! Thank you so much for doing all the work for us and sharing it!
So glad you found this post helpful Mariko! 🙂 It took quite a bit of time to calculate it all! Thank you for sharing!!
Thank you for sharing I make starting to make at home to get really good at it. Made a few petty good but the frosting needs work in the area of the amount to use a 3 layers 3.
Maybe this question is in the comments but I cant find it. How many cups of your american buttercream would I need to achieve the 1/4 inch thickness for the tops and middle of a 3 layer 9 inch cake? Your chart I will need 6 cups of frosting. A cup per layer 3 cups around the side?
Hi Trish,
Great question—and you’re exactly right in your thinking! For a 3-layer, 9-inch cake with frosting between the layers and on top, plus a layer around the sides, 6 cups of buttercream is usually perfect:
About 1 cup between each layer (so 2 cups total for the filling)
1 cup for the top
And 3 cups for the sides to get a nice, smooth finish
If you like a thinner or more rustic look on the outside, you could get away with a little less, but 6 cups is a safe estimate for a classic, well-frosted finish. I usually make a little bit extra because I hate running out and like to have thick layers of frosting between the layers though! You also may want a bit more if you want to pipe decorations around the cake or make a frosting border. Hope that helps, happy baking!
Hi, I just found your website, today, looking for cake recipes, and I’m excited to make yours!!
Do you have a recipe for the buttercream that you use?? Thanks so much!!
Cathy
Hi Cathy,
Welcome, I’m so glad you found my site! Yes, I do have a buttercream recipe that I use for most of my cakes and cupcakes. It’s my go-to American buttercream: super creamy, pipes beautifully, and holds up well. You can find it here: https://chelsweets.com/the-best-american-buttercream-recipe/
However, if you don’t like sweet frosting, you might want to try my hybrid buttercream! It takes a bit longer to make but is also delicious: https://chelsweets.com/not-too-sweet-buttercream-frosting/
Hope that helps, happy baking!!