Essential Oil Dilution Calculator
Blend essential oils into a carrier at a safe strength — how many drops to reach a target dilution, or what dilution the drops you added actually give.
Add this much essential oil
- Children, pregnancy, breastfeeding, sensitive or broken skin: use a lower dilution than the adult ranges and check a reliable source or ask a doctor first. Some oils should not be used at all in these cases.
- Expressed (cold-pressed) bergamot, lime, lemon and grapefruit oils are phototoxic: keep treated skin out of the sun for at least 12 hours, or choose steam-distilled or bergapten-free (FCF) versions.
- Patch test every new blend before using it more widely.
- Stop and wash off at any redness, itching or stinging, and see a doctor or dermatologist if a reaction is severe or does not settle.
That blend is
Maximum safe dilutions vary by oil, age, pregnancy, and where the blend is used. The measured dilution is rounded up, never down. Check a reputable dilution chart, keep facial blends low, and patch test every new blend.
Potent by nature, safe by dilution
Essential oils are among the most concentrated ingredients in natural beauty — a single drop can carry the aromatic compounds of a whole handful of plant material. That potency is exactly why they’re never meant to touch skin neat. Diluting them into a carrier oil spreads those compounds through the blend, so a face oil soothes rather than stings and a body blend nourishes rather than sensitises.
Dilution is measured as a percentage of the finished blend, and the arithmetic is easy to get wrong by eye. This tool does it both ways: tell it your carrier amount and the strength you want and it returns the drops to add; or tell it what you already mixed and it tells you the percentage you landed on.
Frequently Asked Questions
What dilution should I use?
It depends on where the blend goes and who it's for. The Tisserand Institute's published guidelines are 0.5 to 1.2% for facial products, 0.2 to 1% for sensitive or impaired skin, and 1 to 3% for body oils and lotions; this calculator refuses anything above 10%. For children, during pregnancy or breastfeeding, use a lower dilution and check a reliable source or ask a doctor first, because some oils should not be used at all. Lower is safer, and some oils have their own stricter limits: expressed bergamot, lime, lemon and grapefruit are phototoxic, so keep treated skin out of the sun for at least 12 hours.
How does the drops-per-millilitre figure work?
Essential oils are dosed in drops, and a millilitre of a typical thin oil is roughly 20 drops — the value the tool uses by default. Thicker oils and different droppers give larger or smaller drops, so if you have a more accurate figure for your bottle you can enter it to fine-tune the result.
Why dilute at all?
Undiluted essential oils are extremely concentrated and can cause irritation, sensitisation, or burns on skin. Diluting them into a carrier oil spreads the active compounds safely across the blend so you get the aroma and benefits without the risk. It also makes the oils go much further.
Is this a substitute for professional advice?
No. This calculator is an educational tool for blending at safe percentages. It isn't medical or dermatological advice, doesn't account for photosensitising oils or individual sensitivities, and shouldn't guide use during pregnancy, on infants, or on broken skin without qualified guidance. Always patch test a new blend.
Educational estimate only, not medical or dermatological advice. Safe dilutions vary by oil, age, pregnancy, and application site; some oils are photosensitising. Check a reputable dilution guide and patch test every blend.