An essential oil dilution chart turns a percentage into a drop count. On the Tisserand Institute standard of 30 drops per ml, a 1% blend is 3 drops of essential oil in 10 ml of carrier oil, 2% is 6 drops and 3% is 9. The chart below covers 5-100 ml bottles and the right use for each.
A review of contact allergy in the journal Dermatitis found that most allergic reactions to essential oils came from pure oils or high-concentration products (de Groot and Schmidt, 2016). The right percentage is your first safety step, and the second is knowing how to patch test an essential oil before a new blend goes on a large area.
You'll also want bottles that match the rows of the chart, and something that measures in ml once a batch gets big. Both are in the droppers, roller bottles and blending accessories collection.
How many drops of essential oil go in each ml of carrier oil?
At 1% strength, each ml of carrier oil takes 0.3 drops of essential oil. Nobody can measure 0.3 of a drop, so dilution charts work in 10 ml steps instead, adding 3 drops per 10 ml for every 1% of strength. That makes a 5% blend 15 drops per 10 ml. Every figure assumes 30 drops make 1 ml.
Dilution is the share of essential oil in a blend, expressed as a percentage of total volume.
The 30-drop figure comes from weighing. The Tisserand Institute reports three investigations, from 1999, 2000 and 2016, that tested 1, 25 and 23 different essential oils through 3 to 7 styles of dropper. Each time, 20 drops averaged 0.66 g. Thirty drops therefore weigh about 0.99 g, which the Institute treats as a close match for 1 ml (Tisserand Institute, "How big is a drop?").
Some charts online use 20 drops per ml instead, so they show 2 drops per 10 ml at 1% where this one shows 3. Switching between them halfway through a recipe is the mistake, so check which standard a chart states before you trust its numbers.
How many drops go in a 5, 10, 15, 30, 50 or 100 ml bottle?
Multiply the bottle size in ml by 0.3, then by the percentage you want. A 15 ml bottle at 2% takes 9 drops, a 30 ml (1 fl oz) bottle takes 18 and a 100 ml bottle takes 60. The chart rounds down to whole drops, so the smallest bottles come out slightly weaker than their label.
Printable dilution chart (30 drops = 1 ml)
| Bottle size | US equivalent | 0.5% | 1% | 2% | 3% | 5% |
|---|---|---|---|---|---|---|
| 5 ml | about 1 tsp | under 1 | 1 | 3 | 4 | 7 |
| 10 ml | about 2 tsp (1/3 fl oz) | 1 | 3 | 6 | 9 | 15 |
| 15 ml | about 1 tbsp (1/2 fl oz) | 2 | 4 | 9 | 13 | 22 |
| 30 ml | about 2 tbsp (1 fl oz) | 4 | 9 | 18 | 27 | 45 |
| 50 ml | about 1.7 fl oz | 7 | 15 | 30 | 45 | 75 |
| 100 ml | about 3.4 fl oz | 15 | 30 | 60 | 90 | 150 (5 ml) |
How to read it:
- Each number is the total for all essential oils combined, not per oil. The Tisserand Institute's own printable dilution chart counts the same way and rounds down to whole drops just as this one does.
- Rounding bites hardest in small bottles: 5 ml at 1% is really 1.5 drops, so 1 drop gives about 0.7%. Scaling up fixes it. A 0.5% blend is a messy 1.5 drops in 10 ml but exactly 3 drops in 20 ml.
- Past about 30 drops, measure in ml instead. A 100 ml body oil at 3% needs 3 ml of essential oil, which a pipette measures far faster than counting 90 drops.
- The 5% column is for small bottles used on small areas. The Tisserand Institute advises against using the same oil or blend above 5% for months or years (irritation and allergic reactions), so a 100 ml bottle at that strength rarely makes sense.
Which dilution should you use for face, body or a small area?
Use about 1% on the face, 2% for body oils and lotions, and keep 3-5% for small areas over a short time. Those common figures come from the Tisserand Institute's general dilution guide, which gives ranges of 0.2-1.5% for facial products and deodorants, 1-3% for body oils and lotions, and 3-10% for roll-ons.
| Strength | Drops per 10 ml | When to use it |
|---|---|---|
| 0.5% | 1.5 (3 per 20 ml) | Low end of the facial range. A cautious choice for reactive skin, and for older adults, whose skin NAHA notes may be more sensitive. |
| 1% | 3 | Face oils, serums and deodorants. Also the starting point the Tisserand Institute suggests for people with past skin reactions, raising in 0.5% steps only if needed. |
| 2% | 6 | Body oils, lotions and massage blends that cover large areas. |
| 3% | 9 | The top of the body-oil range. Also the common figure for bath products, which need a dispersant before they go in the water. |
| 5% | 15 | Small-area, short-term blends, such as a roll-on used on a few spots. Not for whole-body or month-after-month use. |
NAHA (the National Association for Holistic Aromatherapy) puts most oil-based aromatherapy blends between 1% and 5% and says that range typically isn't a safety concern. It adds that skin reactions become more likely as strength goes up, depending on the oil, where it's applied and the person's own sensitivity.
How do you calculate essential oil dilution for any amount?
Drops = ml of carrier × percentage × 0.3. For 20 ml at 1.5%, a strength the chart skips, that's 20 × 1.5 × 0.3 = 9 drops. To check a recipe someone else wrote, run the formula backward: percentage = drops ÷ (ml × 0.3). Eight drops in a 10 ml roller is about 2.7%.
For larger batches, skip drops entirely: ml of essential oil = ml of carrier × percentage ÷ 100. A 50 ml batch at 2% needs 1 ml of essential oil.
Worked example with a 50 ml body oil at 2%
- Total drops: 50 × 2 × 0.3 = 30 drops, or about 1 ml.
- Split the total between your oils. Say 20 drops of lavender and 10 of Atlas cedarwood. The 2% applies to the whole blend, not to each oil.
- Check each oil against its own limit. Neither lavender nor Atlas cedarwood appears on the Tisserand Institute's list of oils with a topical maximum of 1.5% or less, so 2% total is fine for both.
Mixing the blend so the numbers hold
- Count the essential oil drops into the empty bottle first.
- Top up with carrier oil to the fill line.
- Cap the bottle and roll it gently between your palms to mix.
- Label it with the oils, the percentage and the date.
Filling in that order makes the percentage a share of the finished blend, which matches the definition above. The Tisserand Institute's chart counts drops per volume of base oil instead, and the gap is small: 15 drops (0.5 ml) in 10 ml of carrier is 4.8% of the finished blend rather than 5%. At 3% or less, the difference is under 0.1 percentage points.
How accurate is a drop of essential oil?
A drop is only roughly accurate. In the Tisserand Institute's weighing studies, drops per ml ranged from about 20 to 40 across oils and dropper styles. So 6 drops in 10 ml, mixed as a 2% blend, could really land anywhere between 1.5% and 3%. For home blends that margin is acceptable; for exact work, measure by volume or weight.
The Institute's view is that outside clinical settings with strict controls, the average figure is safe to use. The variation matters more when you scale up or blend for reactive skin.
Two things change the count:
- The dropper. A drop's size depends largely on the opening it forms at, so an orifice reducer and a glass pipette won't necessarily give identical drops of the same oil.
- The oil. Thick oils such as vetiver and sandalwood drip slowly, which tempts people to shake the bottle and add extra.
When accuracy matters, the Tisserand Institute recommends measuring by volume (a pipette marked in ml) or by weight on a scale that reads to 0.01 g, and picking one method per formula rather than mixing them. One useful test: count how many drops from your own bottle fill 1 ml. If it's 40, every number in the chart above gives you a weaker blend than its label.
Do some essential oils need a lower dilution than the chart?
Yes. The chart gives total strength, but several oils carry their own skin limit well under 1%. The Tisserand Institute lists topical maximums of 0.1% for cinnamon bark, 0.5% for clove bud, 0.7% for lemongrass and 0.8% for ylang-ylang, set to limit skin reactions. Inside a blend, each oil's own limit caps how many drops of it you add.
| Oil | Topical maximum | Most drops in 10 ml | Most drops in 30 ml |
|---|---|---|---|
| Cinnamon bark | 0.1% | under 1 | under 1 |
| Clove bud | 0.5% | 1 | 4 |
| Lemongrass | 0.7% | 2 | 6 |
| Ylang-ylang | 0.8% | 2 | 7 |
| Oregano | 1.1% | 3 | 9 |
Source: Tisserand Institute topical maximum tables, drawn from Essential Oil Safety, 2nd edition.
So an 18-drop, 2% blend in a 1 fl oz bottle can still hold no more than 6 drops of lemongrass. Cinnamon bark is stricter still: 0.1% of 30 ml is 0.9 of a drop, so a single drop in a 1 oz bottle already goes over.
A small patch of skin doesn't change these limits. The Tisserand Institute explains that maximums set for skin reactions depend on how concentrated the oil is on the skin, measured per square centimeter, so they apply the same way however much or little skin you cover (Q&A on dermal safety maximums). Dabbing a 5% lemongrass blend on one spot is still 5% lemongrass on that spot.
Sun exposure adds a separate ceiling for certain cold-pressed citrus oils, covered with their own numbers in phototoxic essential oils.
These limits follow specific constituents, such as citral in lemongrass and cinnamaldehyde in cinnamon bark. A GC/MS report shows how much of each your bottle actually contains, and Miracle Botanicals publishes a GC/MS report for every single essential oil on its product page.
When doesn't an adult dilution chart apply?
This chart is built for healthy adult skin. Pregnancy, children, broken or inflamed skin and undiluted use each change the rules. If you're pregnant, have a skin condition, epilepsy or asthma, or take prescription medication, the Tisserand Institute advises talking to a doctor or qualified practitioner before using essential oils on your skin.
- Pregnancy. Some oils are off the list entirely and strengths come down; see essential oils to avoid during pregnancy, and check with your midwife or doctor.
- Children. Safe strengths change with age, so the numbers live in a separate guide to essential oils safe for kids by age.
- Neat use. Putting oil on skin with no carrier at all is its own question, answered in applying essential oils neat.
- Damaged skin. NAHA notes that damaged, diseased or inflamed skin absorbs more oil and reacts more readily, and advises against applying oils to open or damaged skin.
What should you dilute essential oils in?
Dilute essential oils in a carrier oil: a fixed plant oil pressed or extracted from seeds, nuts, kernels or fruit, which doesn't evaporate the way an essential oil does. Plain water won't work. Essential oils float on it in tiny undiluted droplets, which is why drops added straight to a bath can sting sensitive skin.
NAHA also lists unscented natural lotions as a suitable base, and the chart works the same way for them: measure the lotion in ml and count drops as above. Which carrier oil suits your skin type and the texture you want is a bigger question, covered in the guide to the best carrier oil for essential oils.
What's the one number to remember?
Remember 3 drops per 10 ml for every 1%, because every row of the chart grows out of it. Before you mix, check two things: whether any oil in the blend has a lower ceiling of its own, and whether the person using it needs a different chart altogether. Print the chart and keep it with your bottles.
