How Much Essential Oil To Add To Soap

Have you been confused about how much essential oil to add to soap when soaping? It is frustrating to add too much of expensive essential oil and end up with soap with overwhelming scent. And also, it is kinda disheartening to get a beautiful but unscented soap because of adding too little oil in the recipe.

Read on to know how much to add, to get the most bang from your buck, and also save your time.

So, How Much Essential Oil Should I Add to Soap?

While the usage varies based on different essential oils, the usage rate in general, is 3% by weight.

When talking about soap making, I would rather choose weight than drops as a calculating method. It is more accurate and useful to avoid excessive essential oil.

For instance, in a 3lb (1360grams) batch of soap, you can add 3% weight lavender essential oil. 3% of 1360g is 40.8g, which is the maximum amount of lavender essential oil by weight that you can add to the recipe.

The density of this essential oil is 0.905g/ml. Divide 40.8g by this metric, then you will get how many milliliters of oil you can use. And the answer to this math question is 45.08mL. 

The density of essential oils varies, hence the teaspoon amount of each essential oil can be different. And here is the chart of essential oils for soap making.

Essential OilWeight%Weight for 1lb soapApprox amount in tsp
Lavender3%0.48 oz / 13.6g3 teaspoon
Lemongrass3%0.48 oz / 13.6g3 teaspoon
Chamomile3%0.48 oz / 13.6g3 teaspoon
Eucalyptus3%0.48 oz / 13.6g3 teaspoon
2%0.32 oz / 9g2 teaspoon
Rosemary3%0.48 oz / 13.6g3 teaspoon
Tea Tree3%0.48 oz / 13.6g2.5 teaspoon
Ylang Ylang3%0.48 oz / 13.6g3 teaspoon
Note: Essential oil usage in this table refers to computation for 1lb soap making

Note: Some specific essential oils are the exception. The usage of nutmeg should be 0.05%, which is way less than 3% because of the powerful substitute. As for rose otto, the recommended usage is 0.2% due to its strong scent.

Factors that Affect Essential Oils Usage for Soap Making


A factor to consider when you are about to add essential oil to soap is the temperature. Each essential oil has a flashpoint, which is the temperature at which the liquid can ignite with a flame in certain conditions. Some people claim that if the essential oil is heated to the flash point in the recipe, the aroma will decay.

Actually, there is no evidence or scientific studies prove that the scent would fade under much more heat. Having said that, let us take this factor into consideration. It is better safe than sorry, whatever. 

So if you are using essential oil with the low flash point in a recipe, avoid gelling the soap or making hot process soap. Usually, soap would get as hot as 180 ° F in the gel phase. As for the hot process, the soap’s temperature is generally around 160 ° F.


Every essential oil is different and has varying strengths

Another factor is the strength of essential oils. Some essential oils are just strong, so you may need to add less of them in the recipe. If you add too much essential oil, you’ll not only waste money, but your soaps could cause skin irritation and photosensitivity.

The rose essential oil has got an incredibly strong scent and can be overwhelming to our senses. Some scents like clove and cinnamon can cause skin irritation if overused.

The cold process in soaping goes through various pH changes, resulting in a harsh environment for specific essential oils. Some essential oils’ scents, like coconut and citrus (lemon, bergamot, grapefruit, etc.), can fade extremely fast. These oils tend to evaporate very quickly in cold process soap.

For the best scent retention, make sure the essential oil you’re using is from a trustworthy supplier and is approved for use in soap. And ensure that those essential oils get along with the specific soaping process.


Adjust to Your Favorite Amount

Your preference might be the third factor. Some essential oils are mild or exceedingly strong in soap, so you can always adjust the amount of those to your preference. For example, Rose oil is very potent, so you don’t need to apply the usage of rose as much as other essential oils. 

When your soaps are only for individual use, you may adjust the amount based on your own preference on the strength of the aroma. Note down the amounts used and the results after every trial soaping. In this way, you can keep improving the scent combinations and the amounts needed. Always adjust to your personal nose and aroma preference.

Having said that, I would not suggest using that much nutmeg, cinnamon, clove, etc. in a recipe.

Compliance with IFRA Standard(voluntary)

The International Fragrance Association establishes safe usage standards and guidelines for adding essential oils to soap. These guidelines are based on scientific analysis rather than unconfirmed reporting or speculation. While compliance with the IFRA standard is on a volunteer basis, we recommend doing so. We can take those documents into account when soaping, especially those ingredients labeled as prohibited by IFRA.

Three IFRA standards classifications

Prohibited – It means that you should not use the ingredient at all.

Restricted – It means that you may use the ingredient; however, it should only be used below a certain concentration level.

Specification – It means that you should evaluate the purity of ingredients.

how much essential oil to add to soap


More Tips for Soapers

To maximize scent retention during the curing process, store your soap in a cool, dry place and avoid direct sunlight. And there is one more trick to make scents last even longer. You can place a cotton ball saturated with essential oils by the soap while it is curing. This method may help the soap “absorb” some odors in the curing process. Avoid putting the cotton ball on a plastic surface as essential oils may react with plastics.

Many white cottage manufacturers still make essential oil soaps in their own kitchen or their own houses. You may need to take extra precautions to protect others who may encounter your raw materials. Store your essential oils out of reach of your children and pet to keep them safe. Lock and key would help you deny any unexpected access to your essential oils collection.

No block ID is set

Shop By Catalog

Leave a Reply

Your email address will not be published. Required fields are marked *