How Much Frosting Needed For A Full Sheet Cake

The historic period quondam question…how much buttercream do I need?? For a batch of cupcakes? A half dozen-inch layer cake? For a nuptials cake?!

This post shares everything y'all need to know to brand the perfect amount of frosting for any baking project. It's basically the frosting version of my cake batter estimator.

The amount of frosting you demand varies based on the following factors:

Size of cake layers
Shape of block layers
Number of block layers
Decoration style (semi-naked, smooth, buttercream rosettes, large swirls on top, on etc.)

With the assistance of my buttercream formula and chart below, you'll exist able to effigy it out in a snap!

image of a buttercream cake being frosted with sharp edges and smooth sides to show How to Frost a Cake Smoothly

Does It Matter What Type of Buttercream I'm Using?

This guide can be used for pretty much whatsoever type of frosting. Whether you're using American, Swiss, Italian, Russian, or fifty-fifty German, a cup of frosting is a cup of frosting.

My only notation on this is that I detect I sometimes need a tiny bit more than American buttercream to make a perfectly smooth cake.

If I'thou using a meringue based frosting, it ordinarily is a chip easier to smoothen 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 summate.

To know how much frosting we'll need, we need to utilize the formula of a cylinder, the formula of a circumvolve, 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 circumvolve ten thickness of the layer of frosting x number of layers) + (surface expanse of a cylinder minus top and bottom)) / by cubic inches per cup

Or in terms of numbers for a 6 inch, ii layers cake, this meant:

Cups needed =((pi x r in² x .33 in 10 2) + (2 10 pi x r in x h in ten .25 in))/14.4 in³

I had to brand 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 volition be about i/three inch thick.

This is based on how I really decorate my cakes! I dearest thick layers of frosting inside, merely like in my expiry by chocolate cake shown above.

However, if you apply 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 demand to be adapted.

If y'all aren't a big fan of math, don't worry! I've used this formula to create a chart below that'due south super easy to utilize. It'll instantly tell you how much buttercream y'all demand 🙂

Step 1: How Large is the Cake You're Making?

The size, shape and number of cake layers will impact how much frosting yous need.

In general, I find one batch or nearly six cups of frosting is the perfect amount for a 7-inch or eight-inch layer cake that's busy with buttercream swirls on top.

I ordinarily take a tiny bit leftover, but it's just about right. This makes sense based on my calculations below!

image of a gluten free funfetti cake that's been decorating with buttercream stripes and a pink drip

Pace 2: Use My Buttercream Computer to Effigy Out How Much Frosting You lot Demand

Based on the size of your cake, utilize the charts below to figure out how much frosting y'all demand. This is just to fill, crumb coat, and embrace a layer cake.

Add an addition 1-2 cups of frosting to the numbers below if you lot desire to pipe big buttercream swirls on summit of the block.

Or if y'all want to brand a frosting intensive design similar roofing a cake in buttercream rosettes, add an additional two-3 cups of frosting for a cake ranging from 6-8 inches. It sounds insane, simply those designs require so much extra frosting!

image of a chart showing how much buttercream you need to frost a cupcakes

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 most 6 cups of frosting.

image of naturally grey buttercream frosting made with black cocoa powder

All the same, it can vary based on the recipe you're using.

Most recipe cards list the yield at the top of the recipe menu, or will share information technology in the notes department at the lesser of the recipe card.

Now that you know how many cups of frosting you need, you can back into how many batches of frosting y'all'll need to make.

And just like that, you're ready to make the perfect corporeality of frosting!!

I'd love to hear if you found this postal service helpful, or if you end up utilize information technology! Tag me @chelsweets and #chelsweets on social media.

You tin also download the charts above here!