Tool
Essential Oil Dilution Calculator
Choose a carrier amount and a strength, and see how many drops of essential oil that means, with the usual limits for face, body and children.
Drops at a glance
Drops of essential oil for common bottle sizes, counting 20 drops to 1 ml. Half drops are rounded to the nearest half; above 10 drops, to the nearest whole drop.
| Carrier oil | 0.5% | 1% | 2% | 3% | 5% |
|---|---|---|---|---|---|
| 5 ml | ½ | 1 | 2 | 3 | 5 |
| 10 ml (roller) | 1 | 2 | 4 | 6 | 10 |
| 15 ml (1 tablespoon) | 1½ | 3 | 6 | 9 | 15 |
| 30 ml (about 1 fl oz) | 3 | 6 | 12 | 18 | 30 |
| 50 ml | 5 | 10 | 20 | 30 | 50 |
| 100 ml | 10 | 20 | 40 | 60 | 100 |
How this works
A strength in percent is the share of essential oil in the carrier: 2% of 10 ml is 0.2 ml. The calculator turns that into drops using the common working figure of 20 drops to 1 ml, so one drop is 0.05 ml. The same figure sets the strengths printed on our blend recipes. In the other direction, it divides your drops by 20 to get millilitres and compares them with the carrier.
The five strengths and who they suit follow the ranges in NAHA's and the Tisserand Institute's dilution guidance. When you choose an oil, the calculator checks the strength against the skin maximum on that oil's reference page and repeats its notes on sunlight, pregnancy and children. To balance several oils and check each one's share, use the blend builder.
Assumptions and limits
- Drop size varies with the dropper and the oil: thin citrus oils fall in smaller drops than thick ones such as vetiver or sandalwood. Real droppers give anywhere from about 20 to 40 drops per millilitre, so a drop count is an estimate and erring low is the safe side.
- We take the percentage against the carrier amount. Strictly it is a share of the finished blend, which is a touch weaker: 0.2 ml in 10 ml of carrier is 1.96% of the 10.2 ml you end up with.
- The strengths are for skin. Diffusers are measured in drops and minutes, not percent; a bath needs the oils mixed into a carrier oil or unscented bath gel first.
- Skin maximums apply to each oil on its own. A strength that is fine for lavender can be far too strong for bergamot, lemongrass or clove.
- Children under 2, pregnancy and broken, inflamed or very sensitive skin call for extra care. When in doubt, choose the gentler strength and ask a clinician.
Questions
- How many drops of essential oil go in 10 ml of carrier oil?
- At 2%, the everyday adult strength, 4 drops. At 1% it is 2 drops, and at 3% it is 6 drops. These figures count 20 drops to 1 ml, the usual working figure; your dropper may give smaller drops, so stay at or under the number rather than over it.
- What dilution should I use on my face?
- Keep facial blends at 1% or less: about 2 drops in 10 ml of carrier oil. Facial skin is thinner and more reactive than skin on the body, and the face is close to the eyes and nose.
- Does the strength apply to each oil or to the whole blend?
- The strength is for all the essential oils together. If a blend mixes three oils at 2%, the three share those drops between them, so each oil sits well under 2% on its own. The blend builder works out each oil's share and checks it against that oil's own skin maximum.
- Why does the result sometimes show half a drop?
- Small bottles at gentle strengths can call for 1.5 or 2.5 drops. Half a drop cannot be measured, so either make twice the amount and use the doubled drop count, or round down, which gives a slightly gentler blend.
Sources
- Dilution for essential oils, Tisserand Institute. Accessed October 26, 2026
- Safety, National Association for Holistic Aromatherapy (NAHA). Accessed October 26, 2026
- Safety guidelines, Tisserand Institute. Accessed October 26, 2026
- Aromatherapy and pregnancy guidelines, International Federation of Professional Aromatherapists (hosted by NAHA). Accessed October 26, 2026