We have a really cool essential oil section in the Soap Making Resource warehouse where I can work on new natural aroma combinations to my heart’s content. At Soap Making Resource, we carry more than 45 therapeutic grade essential oils as part of our soap making supplies inventory, so there are a ton of great scents that I can play with!

Here’s a picture of me in the warehouse working on an essential oil blend:

So, have you ever seen essential oil blend recipes that look something like this:

3 parts X essential oil

7 parts Y essential oil

2 parts Z essential oil

I’m finding out that many soap makers just don’t know how to transfer information like the above into usable essential oil proportions.

Luckily, I love math… and I love teaching! So let me give you a brief explanation on how the above blend works:

Let’s say your blend is 3 parts bergamot essential oil, 7 parts grapefruit essential oil and 2 parts peppermint essential oil. Now for your soap batch, let’s say you want to create 3 ounces of essential oils total. By the way, I usually use 3 ounces for a 6 pound batch. How do you know how much of each essential oil to include in your blend if you want to use the above recipe?

Well… the above “parts” tells you exactly that!

Let’s look carefully at the recipe. You can see above that the entire recipe is made up of 12 parts. 3 parts plus 7 parts plus 2 parts equals 12… right?

So now, all you have to do is find out what percentage the different essential oils make up. 3 parts bergamot essential oil would be 25%. Why? Because 3 parts divided by 12 parts equals .25 or 25%. So now we know that 25% of the 3 ounces is going to be made up of bergamot essential oil. 25% of 3 ounces is .75 ounces.

Using the same formula, we can see that 7 parts grapefruit essential oil would make up 58.3% of the blend. We know this because 7 parts divided by the total 12 parts equals .583 or 58.3%. 58.3% of 3 ounces equals 1.75 ounces.

Finally, we have 2 parts peppermint essential oil. 2 parts peppermint essential oil means that peppermint will take up 16.66% of the blend. 16.66% of 3 ounces equals .5 ounces.

If you add up the amounts for all three essential oils, you will see that .75 ounces plus 1.75 ounces plus .5 ounces equals your total 3 ounces of essential oils. It’s very easy when you think about it!

I will tell you that when using ounces to measure your essential oils, you will be almost forced to round your numbers. Unless you have an AMAZING scale, you probably won’t be able to accurately measure 1.749 ounces of an essential oil. You will have to round to 1.75 ounces. If you want to be more accurate, measure in grams as I do! The process is exactly the same, just use grams instead of ounces.

Now… If you want to experiment with different essential oil blends, just take a pipette and drop your essential oils of choice onto a piece of paper towel. Put the paper towel in a jar and close the lid. Let it set for a few days to give the aroma time to mellow out. Each drop of essential oil represents 1 part.

Once you come up with a scent that you like, simply use my method above to create a batch of it that’s large enough to use in your soaps. Whether you need 3 ounces 6 ounces or 25 pounds of a blend, you can use my method to figure out how much of each essential oil to use.

Have fun exploring all the wonderful natural aromas that are out there!

Thanks for the tutorial. I guess that I do my math backwards. I add all the parts together, 3+7+2=12. then divide my desired quantity by how many total parts 3oz/12= .25. This tells me how much each unit equals, then I multiply the units by how many parts .25×3=.75, .25×7=1.75, 2x.25=.5. Then I check my math .75+1.75+.5=3oz. It never occured to me to do it the way you described. This is why forums are so important.

Hi Janean! Yeah… this method works too The forum will be up soon I hope. You are right… forums are so important because there are so many ways to do the same thing and often all of them are correct. Your math method may make more sense to some soap makers and that is totally awesome! It would be great if we can all share our knowledge together!

You commented that, “3 ounces for a 6 pound batch” is what you use. When you say “6 pound batch” you’re just referring to the ounces of carrier oils, correct?

THANKS so much for the helpful tutorials!

Hi Tori! No… when I say 6 pound batch, I mean 6 pounds of actual soap. To make 6 pounds of soap, you need to use about 64 ounces of oil. Then once the lye and water is added, you have 6 pounds of soap.

Hi!

I guess I do my blending the artistic way and not the logical way. I put this and that together and see how it turns out. I do I try to keep the percentage of the oil to the total weight of ingredients around 5%. LOL

Most all of my blends in soap turn out wonderful! Even though you would not think they would. I have noticed when I found a blend I liked and used a recipe from someone else, it did not always smell the same in the soap. Dawn

Hi Dawn! Thanks for your comments Do you have a way to replicate the blend if you fall in love with it? That’s why I love the “parts” method as described in this post. It enables you to duplicate any blend in any amount if you come up with something you like.

You also look like you need a taller table. LOL

Yeah… I’m kind of tall

Hi, am new to the soap game & have been wondering about eo,s & where to find out the allowable pecentages for the restricted ones & also how to work out exactly how much to use in blends as it seems certain oils are much lower in the scale of whats allowed than others due to the allergens contained. I don’t yet have my assessment done due to complications of this country suddenly requiring the new “2013 format” already, so find myself held back from making stuff till I can be sure of this info. Seems a bad time in soap history to be starting up in this venture in the E,U

Thanks for the maths lesson it will come in handy

Glad to hear the math lesson will help! As for your question, I would check out IFRA… that’s International Fragrance Association for regulations. Their website is ifraorg.org. Hope this helps!

I have been making soap for several years and have always been a ‘loner’ for my soapmaking. I stumbled on the website and I think I am going to love it! I just don’t have anyone to talk soap to about, for ideas, tips. Just a trial and error. Nice to know that during this time I make a 6# batch and use 3 oz of essential oil! I must have read that ratio somewhere!! My soap always turns out great and the scents last. Anyone use orris root in soap??? or other fixative??? That has always been a big question for me, and if so, how much?

And yes, you need a taller table!!! good body mechanics!!

I will certainly be reading these forms/blogs and asking questions from time to time. Thanks for this website.

Janis

I was wondering about using a fixative for fragrances as well. Are there certain EO’s that require it, and others that don’t need it? What are the best ones to use if they are required at all?

Janean

This is a great tutorial for making soap using essential oils. Math is a useful and necessary skill in almost every industry. Remind me to tell my kids that again!

Hi Steve and all you wonderful soapers out there. I just wanted to say how much I have learned from Steve. He cuts through the junk and gets you clearly to what you need. If you are new or old to soap making, you have to have this guy as one of your mentors, he is super. Thanks to you Steve, for getting me out of more messes than I ever thought I could get into, with soap that is!!!!

Judy

Steve, I was really grateful for this tutorial and I use it for most of my formulations. However, is it okay to use equal parts of the 3 oils? I’m guessing that it is, because that is how I used to do it, but I decided to stick with the parts method. Now, I still want to ask if would be okay to use equal parts of four EOs in a blend. And, how does one know the maximum amount of EOs to use for a 3lb batch? I use your wooden mold so that’s what my guide is. Thanks!

Hi! I am new to making soap but really a bit nervous about all the measurements as I was never a math wiz.

Is there any easy way to measure oils essential oils

without all the math formula’s? Thank goodness there

are the lye calculators I’d be there all day figuring

those out! Nina