Essential oils are diluted with carrier oils, which are mild, plant-based oils that reduce the concentration of essential oils before they touch your skin. The most popular choices include jojoba oil, sweet almond oil, coconut oil, and grapeseed oil. Without dilution, many essential oils are concentrated enough to cause skin irritation, redness, or even chemical burns on direct contact.
Carrier oils aren’t the only option, though. Depending on what you’re making, you might also use alcohol, aloe vera gel, or unscented lotion as a base. Each diluent works differently and suits different purposes.
Carrier Oils: The Standard Choice
Carrier oils are the go-to diluent for essential oils applied to skin. They’re pressed from the fatty parts of plants (seeds, nuts, kernels) and have large triglyceride molecules that slow the evaporation of the volatile essential oil compounds, keeping them in contact with your skin longer. Contrary to a common belief, carrier oils don’t actually push essential oils deeper into your skin. They simply provide a safe, spreadable base.
Here are the most widely used carrier oils and what makes each one different:
- Jojoba oil absorbs quickly, doesn’t feel greasy, and won’t clog pores. It works well for facial blends and is one of the most shelf-stable options, lasting about two years.
- Sweet almond oil is lightweight and moisturizing, a solid all-purpose choice for massage blends and everyday skin care. It lasts about one year after opening.
- Coconut oil (virgin) is rich in fatty acids and polyphenols, making it popular for body massage. It’s solid at room temperature and melts on contact with skin. Virgin coconut oil lasts three to five years, longer than almost any other carrier oil.
- Grapeseed oil is very light with a neutral scent, rich in vitamin E, and absorbs quickly without leaving a heavy residue.
- Apricot kernel oil is high in fatty acids and vitamin E with a faintly sweet, nutty scent. It absorbs easily and works well for facial applications.
- Argan oil is rich in vitamins A and E, with a nutty aroma. It suits most skin types and has a shelf life of about 1.5 to 2 years.
- Rosehip oil is high in vitamins A and C, making it a popular pick for anti-aging blends.
- Avocado oil is thick and heavy, best suited for very dry or damaged skin. Its richness makes it better for body use than facial application.
- Sunflower oil is gentle and affordable. It helps form a protective barrier on irritated skin.
- Olive oil is easy to find in any kitchen, packed with fatty acids. It’s heavier than some options but works fine for body blends.
How to Choose a Carrier Oil for Your Face
If you’re blending essential oils for facial use, pore-clogging potential matters. Oils are rated on a comedogenic scale from 0 (won’t clog pores) to 5 (almost certainly will). For oily or acne-prone skin, stick to oils rated 0 to 2. Argan oil and safflower oil both score a 0. Grapeseed, rosehip, and pomegranate seed oil score a 1. Jojoba, sweet almond, and apricot kernel oil score a 2.
Coconut oil, despite its popularity, scores a 4 on the comedogenic scale. It’s better reserved for body use. The same goes for avocado oil (rated 3), cocoa butter (rated 4), and soybean oil (rated 4 to 5). If you have dry or normal skin, you can generally tolerate oils up to a rating of 2 or 3 on your face without issues, but if you’re breakout-prone, lower is safer.
Dilution Ratios That Actually Matter
The standard dilution for adults applying essential oils to the body is 2%, which works out to about 12 drops of essential oil per ounce (30 mL) of carrier oil. That’s the ratio most aromatherapists recommend for everyday use.
For context, here’s how the common dilution levels break down per ounce of carrier oil:
- 1% (gentle, for sensitive skin or facial use): 6 drops per ounce
- 2% (standard for body application): 12 drops per ounce
- 5% (short-term or targeted use only): 30 drops per ounce
If you’re working with smaller amounts, the math scales down simply. For one teaspoon (5 mL) of carrier oil, a 2% dilution is just 2 drops. For one tablespoon (15 mL), it’s 6 drops.
A 1% dilution is a better starting point for facial skin, for children over age 6, and for anyone with sensitive or reactive skin. The 5% concentration is reserved for short-term, localized applications like a sore muscle blend you’d use for a few days, not something you’d apply daily over large areas.
Non-Oil Diluents: Alcohol, Aloe, and Lotions
Carrier oils aren’t your only option, especially if you’re making a spray, a bath product, or something that needs a lighter texture.
Unscented lotion or cream works as a base for essential oils in much the same way carrier oils do. You add your drops to the lotion and mix thoroughly. This is convenient if you want a scented moisturizer without the oily feel, and the same dilution ratios apply.
Aloe vera gel can also serve as a base, particularly for after-sun blends or lighter skin applications. Essential oils don’t fully dissolve in aloe (it’s mostly water), so you’ll need to stir or shake the blend before each use.
For room sprays and body mists, alcohol is the proper solvent. Essential oils don’t dissolve in water. They float on the surface, which means a “water and essential oil” spray delivers uneven, potentially irritating bursts of undiluted oil. To properly dissolve essential oils into a water-based spray, you need high-proof ethanol, specifically 190-proof grain alcohol (95% ethanol). Regular vodka at 40 to 50% alcohol content won’t fully solubilize the oils, despite being commonly recommended online. If 190-proof isn’t available in your area, 151-proof (about 75% ethanol) is a workable but less effective substitute.
Witch hazel is sometimes suggested as a spray base, but it’s mostly water with a small percentage of alcohol. It won’t dissolve essential oils on its own. You’d still need to add a solubilizer or accept that the blend will separate and require shaking.
How to Store Carrier Oils
Carrier oils go rancid. Most last 12 to 24 months unopened and 6 to 12 months once you break the seal. Temperature, light, and air exposure all speed up oxidation, which breaks down the beneficial compounds and can create byproducts that irritate skin.
Store your carrier oils in dark glass bottles, in a cool place away from direct sunlight. A cabinet or drawer works well. Refrigeration can extend the life of oils that oxidize quickly, like grapeseed and rosehip.
You’ll know a carrier oil has turned if it smells sour or “off,” looks darker than it did when new, or appears cloudy or separated. Golden or amber-colored oils that have gone rancid often darken to brown or near-black. If your oil smells or looks wrong, replace it. Applying a rancid oil to your skin can cause irritation regardless of what essential oil you’ve mixed into it.
Jojoba oil is technically a liquid wax, not a true oil, which is why it resists oxidation better than most options and lasts about two years. Virgin coconut oil is another long-lasting choice at three to five years. If you don’t use carrier oils frequently, these are the most practical options to keep on hand.