How to Dilute Essential Oils: A Simple Chart and Blending Guide

Essential oils are highly concentrated plant extracts. A single drop can hold the aromatic compounds of a large amount of plant material, which is why they are almost never used straight on the skin. Diluting them in a carrier oil makes them safer and easier to spread, and it usually makes them last longer too. This guide explains how to dilute essential oils, gives a simple chart and covers the basics of blending your own scents.

Why dilution matters

Undiluted essential oils can irritate the skin, cause chemical burns and, over time, lead to sensitization, which is an allergic reaction that can return every time the oil touches the skin, even in small amounts. Once someone is sensitized to an oil, they often have to avoid it for good. Dilution greatly lowers these risks. More is not better: a well-diluted blend smells just as pleasant and is far kinder to skin.

Choosing a carrier oil

A carrier oil is a plain, mild vegetable oil that “carries” the essential oil onto the skin. Common choices include:

• Jojoba: technically a liquid wax. It is light, keeps well and suits most skin types.
• Sweet almond oil: a classic massage oil. Avoid it if anyone using the blend has a nut allergy.
• Fractionated coconut oil: stays liquid at room temperature, is light and has little scent.
• Sunflower or grapeseed oil: inexpensive, light options from the grocery store.

Buy carrier oils in small amounts and store them away from heat, because they can go rancid. Unscented lotions or creams can also be used as a base.

Dilution chart

The chart below uses the common estimate of about 20 drops per milliliter. Drop sizes vary between bottles, so treat the numbers as a guide, not an exact measure.

• 0.5 percent: about 1 drop per 2 teaspoons (10 ml), or 3 drops per 30 ml (1 fl oz). Used for sensitive skin and for older children, only when a pediatrician agrees.
• 1 percent: about 1 drop per teaspoon (5 ml), or 6 drops per 30 ml. A good everyday level for the face and for larger areas of the body.
• 2 percent: about 2 drops per teaspoon, or 12 drops per 30 ml. A common level for adult massage and body blends.
• 3 percent: about 3 drops per teaspoon, or 18 drops per 30 ml. Used for short-term use on a small area in healthy adults.

Higher strengths are sometimes used for very small areas for a short time, but they raise the risk of irritation. If in doubt, choose the lower number.

Matching the strength to the use

• Face: 0.5 to 1 percent.
• Body and massage oils: 1 to 2 percent.
• A small area, short term: up to 3 percent for healthy adults.
• Pregnancy, older adults or sensitive skin: stay at the low end and ask a doctor or midwife first.
• Children: many oils are not suitable for children at all. Read essential oils and kids and talk to a pediatrician before using any oil on a child. Do not use essential oils on babies’ skin.

Oils that need extra care

Some oils need lower dilutions or should be kept off the skin entirely:

• “Hot” oils such as cinnamon bark, clove, oregano and thyme can irritate even when diluted. Many people keep them for diffusing only.
• Menthol- and cineole-rich oils such as peppermint, eucalyptus and rosemary are usually kept around 1 percent on adult skin and should not be used on or near the face of young children.
• Phototoxic citrus oils: cold-pressed bergamot, lemon, lime and grapefruit oils can cause burns or dark patches when skin is exposed to sunlight. Keep treated skin out of the sun for at least 12 hours, or use steam-distilled or “bergapten-free” versions.

How to patch test

Before using any new blend, put a small amount on the inner forearm and cover it with a bandage. Wait 24 hours. If there is any redness, itching, swelling or burning, wash the area with soap and water and do not use that blend. Stop using any blend that causes irritation later on.

Essential oils in the bath

Essential oils do not mix with water. Drops added straight to the tub float on top and can land on the skin undiluted. Instead, mix a few drops into a tablespoon of carrier oil or an unscented bath gel or shampoo first, then add it to the water and swish well. Bath oils make the tub slippery, so take care getting in and out.

Blending basics

Blending is where essential oils get fun. A few simple rules help:

• Start with three oils. It is easier to see what works, and easier to fix a blend that is off.
• Think in notes. Top notes such as citrus and peppermint are bright and fade fast. Middle notes such as lavender, chamomile and geranium form the heart of a blend. Base notes such as cedarwood, patchouli and frankincense are deep and long-lasting.
• Test on paper first. Put a drop of each oil on separate paper strips, hold them together and sniff. Adjust the ratio before mixing a full bottle.
• Write everything down. Note the oils, the drops and the carrier, so a blend you love can be made again.
• Let it rest. Many blends change over a day or two as the oils settle.

For diffuser blends, no carrier oil is needed; see using essential oils in a diffuser.

Storing your blends

Use clean dark glass bottles, label each one with the contents and the date, and keep them in a cool place away from sunlight, children and pets. Diluted blends generally keep for several months, depending on the carrier. Throw out any blend that smells rancid or different. The site’s essential oil safety rules cover storage and safe use in more detail. Remember that essential oils, diluted or not, should never be swallowed.

Frequently asked questions

How many drops of essential oil go in 1 oz of carrier oil?

For a 2 percent adult body blend, about 12 drops per 30 ml (1 fl oz). For the face or sensitive skin, use about 3 to 6 drops.

Can water be used to dilute essential oils?

No. Oil and water do not mix, so the essential oil stays concentrated. Use a carrier oil or an unscented lotion.

Is any essential oil safe to use undiluted?

It is safest to assume none are. Even gentle oils like lavender can cause irritation or sensitization when used neat, especially over time.

Do diluted oils still work for scent?

Yes. Diluted blends still smell lovely, and they last longer on the skin because the carrier slows evaporation.

Can blends be used on pets?

No. Do not apply essential oils to pets. See are essential oils safe for pets for details.