Recipe scaling is something I get a reasonable amount of questions about, so I thought I’d write out a how-to on how to scale any recipe so you can confidently make lots (or very little) of the things you love. I’ve also created a downloadable spreadsheet that you can input your data into, and it’ll do all the math for you (score!). Grab that, and the instructions to use it, at the end of the post.
- Your numbers are unlikely to be pretty, so a scale that is accurate to one or two decimal points is a good investment.
- The ratios of the ingredients to one another must remain the same.
- Yes, you must scale everything. Imagine if you scaled up a recipe for a chocolate cake but didn’t increase the amount of sugar or the amount of oil! I’m often asked if the preservative or emulsifier are exempt from scaling: they are not! Nothing is.
- Working in weight is essential for accurate results. If you want to do something simple where precision isn’t imperative, like doubling a face mask recipe that’s in tablespoons and teaspoons, that’s generally fine, but if you’re working with a larger scaling factor, an emulsion, body butter, cosmetics, soap, or pretty much anything else—weight is a MUST.
Step 1: If it isn’t in weights already, convert it to weights
Using grams or ounces, weigh out all the things in the amounts originally specified in the recipe (so if it’s 2 tbsp beeswax, weigh out 2 tbsp beeswax) and make note of all those weights. This applies to essential oils, too, but I know this can be hard if you don’t have a really accurate scale. If you have to, and you’re only scaling the recipe up or down by 1–3, you can get away with continuing to use drops, but if you’re getting to a point where you’re using 40+ drops of an essential oil, you really should be converting that to weights.
Step 2: Convert those weights to percentages
Add up all the weights of all the ingredients to get your total recipe yield. Then, divide the weight of each ingredient by the total yield to get the percentage of each ingredient. Spreadsheets are super useful for this!
Example: If a recipe makes 70g, and has 13g of beeswax in it, divide 13/70. 13 ÷ 70 = 0.1857. So, the recipe is 18.57% beeswax.
Step 3: Scale away!
Now that you have the percentages, you can scale the recipe to your heart’s desire—within the accuracy limits of your scale, at least. Trying to make a 3g batch if something with a scale only accurate to 1g is not going to work out particularly well! To scale, multiply the desired weight of the new batch size by the percentage that ingredient appears in that recipe.
Example: Let’s say we’re scaling the recipe with the beeswax from above, and instead of make 70g you want to make 30g. 30 × 0.1857 = 5.57. So, to make a 30g batch you’ll need 5.57g of beeswax.
Here’s a helpful spreadsheet
Here’s a rundown on how it works (click the image to see a full size version):
Enter the ingredient names in this column.
Enter the weights of the ingredients in this column; you can use grams or ounces, but you must use weight units. These amounts will add up to create the value in cell B13, which is the total weight of the final product.
This column calculates the percentage of each ingredient based on the total size of the recipe. Each of the values in this column are calculated by dividing the weight of the ingredient (10g for beeswax) by the total weight of the product (49.25g). So, for beeswax that’s 10/49.25 = 20.3%.
These are our scaling columns. You can edit the values in cells D2, E2, and F2 to reflect the size of the batch you want to make, and the resulting values in the column below will automatically change.