# FRAGRANCE OIL MATH HELP

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#### Meldoesasoapy

##### Member
I never actually learned the math behind figuring out how much FO needs to go in my CP soap. So far I've just been putting it into the Brambleberry Fragrance Calc with a scent close enough to whatever I'm actually using (using Sage from Aztec Candle but I just chose Juniper Sage FO on Brambleberry Calc cause I figure it's close enough),with the full batch yield weight and using whatever it says the strong is (picture example attached)
I'm hoping to see actual math shown because it's so confusing... here's my basic recipe:

Olive: 7.8 oz (30%), palm: 7.8 oz, coconut:7.8 oz, sweet almond: 2.6 oz (10%), lye: 3.74 oz, water: 8.37 oz
Oil total is 26 oz.
Batch yield is 38.09 oz

So how do I figure out how many ounces of FO goes into it? I'm using Sage from Aztec candle and there's no percentage indicator.

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#### DeeAnna

##### Well-Known Member
First off, what are the recommended guidelines for the particular FO you're using? You need to know that for each of your FOs before you can go further. Brambleberry has all that info built in, so their calc does the thinking for you, but once you get away from BB, you usually have to figure that out on your own.

Some suppliers will give you a max recommended percentage or give you the IFRA guidelines for each FO. Nature's Garden Natures Garden Wholesale Candle & Soap Making Supplies-Fragrance Oils is one company that does both. Some don't tell you anything.

Most soap makers base their fragrance weight on the weight of fats, not total batch weight. If you want to use total batch weight, that's fine too, but you need to account for the weight loss of your soap during cure. Your fragrance must be at a skin safe amount at the time the soap is used, so you really don't want to base your FO weight on the starting batch weight.

If you have a fragrance dosage in percent, then --

Weight of FO = Weight of fats X Fragrance dosage / 100

Whatever units of weight your fats are in will be the units of weight of the FO.

Based on the fat weight of your batch from Post 1 and assuming a fragrance dosage of 6% --
Weight of FO = 26 oz X 6 / 100 = 1.56 oz

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#### dibbles

##### Supporting Member
Supporting Member
If the supplier doesn't give you the IFRA information for soap (category 9), email them and ask. They should be able to provide it. If they can't, or won't, I wouldn't order from them again. Sometimes you might be just fine subbing one FO for another in a fragrance calculator, but not always. And if this company caters to mainly candle makers, I'd be careful doing that.

#### Meldoesasoapy

##### Member
First off, what are the recommended guidelines for the particular FO you're using? You need to know that for each of your FOs before you can go further. Brambleberry has all that info built in, so their calc does the thinking for you, but once you get away from BB, you usually have to figure that out on your own.

Some suppliers will give you a max recommended percentage or give you the IFRA guidelines for each FO. Nature's Garden Natures Garden Wholesale Candle & Soap Making Supplies-Fragrance Oils is one company that does both. Some don't tell you anything.

Most soap makers base their fragrance weight on the weight of fats, not total batch weight. If you want to use total batch weight, that's fine too, but you need to account for the weight loss of your soap during cure. Your fragrance must be at a skin safe amount at the time the soap is used, so you really don't want to base your FO weight on the starting batch weight.

If you have a fragrance dosage in percent, then --

Weight of FO = Weight of fats X Fragrance dosage / 100

Whatever units of weight your fats are in will be the units of weight of the FO.

Based on the fat weight of your batch from Post 1 and assuming a fragrance dosage of 6% --
Weight of FO = 26 oz X 6 / 100 = 1.56 oz

So I found the IFRA statement for the FO I'm using and it said, 5% and above no restriction. So then is it just a matter of how strong you want the scent? I like it pretty strong but don't want to over do it

#### DeeAnna

##### Well-Known Member
Theoretically yes you can use enough to get the strength you want. But there's a practical limit for what will work well in soap. Please read the articles in the link I provided -- this issue is covered in the articles. Here's an excerpt that directly applies --

"...I normally scent my soap at 5% to 6%, assuming the IFRA guideline allows. On occasion, I will use more if I am scenting only part of the soap, but I limit the rate to 8% maximum in the scented portion. The few times I have added fragrance above 8%, the fragrance has weeped out of the soap with unattractive results.

Other soap makers tell me they do not have trouble when they add fragrance at higher percentages, again assuming the IFRA guideline allows, so be aware this 8% limit is my rule of thumb, not anyone else's.
..."

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#### Meldoesasoapy

##### Member
Theoretically yes you can use enough to get the strength you want. But there's a practical limit for what will work well in soap. Please read the articles in the link I provided -- this issue is covered in the articles. Here's an excerpt that directly applies --

"...I normally scent my soap at 5% to 6%, assuming the IFRA guideline allows. On occasion, I will use more if I am scenting only part of the soap, but I limit the rate to 8% maximum in the scented portion. The few times I have added fragrance above 8%, the fragrance has weeped out of the soap with unattractive results.

Other soap makers tell me they do not have trouble when they add fragrance at higher percentages, again assuming the IFRA guideline allows, so be aware this 8% limit is my rule of thumb, not anyone else's.
..."
That makes sense! I still stuck with about 6%, so it should be plenty! I really appreciate your help!