Top, Middle and Base Notes: How to Blend Essential Oils

Smell a few bottles one after another and you will notice something. Some oils seem to leap out of the bottle, while others take a moment to arrive and then stay with you. That difference in speed is the whole idea behind top, middle and base notes. Once you can notice it, blending stops being guesswork.

This guide covers how the three groups behave, a simple ratio to start from, how to test a blend without wasting oil, and how dilution keeps whatever you make comfortable on skin. At the end is an essential oil blending chart of all 47 oils in our reference, sorted by note.

What a “note” actually is

Perfumers borrowed the language of music, but what a note really describes is evaporation. Every essential oil is a mix of many aromatic molecules. Small, light ones evaporate quickly, so you smell them first and lose them soonest. Larger, heavier ones lift off slowly and can still be smelled hours later.

An oil’s note is shorthand for where most of its scent sits on that timeline. In our reference, oils fall into three groups:

• Top notes are bright and quick. They make the first impression and are the first part of a blend to fade. Most citrus oils, peppermint and eucalyptus are top notes in our reference.
• Middle notes, sometimes called heart notes, appear once the top notes settle and carry the blend from there. Florals, herbs and most spices sit here, for example lavender, geranium, rosemary and ginger.
• Base notes are slow, deep and long lasting. Woods, resins and roots such as frankincense, sandalwood, vetiver and patchouli give a blend weight and help the lighter oils linger.

The boundaries are soft. Some charts call lavender a top note and ylang-ylang a base note, and both views have a point. Treat the groups as a guide to how an oil behaves, not a strict classification. If you smell an oil differently from a chart, trust what you notice and plan around it.

A starting ratio: 30/50/20

For a blend that opens brightly, holds together and fades gently, start with roughly 30% top notes, 50% middle notes and 20% base notes, counted in drops. It is the starting guide we use across the site, not a rule.

In a 10-drop test batch, that means 3 drops of top notes, 5 drops of middle notes and 2 drops of base notes.

Each group gets its share for a reason. Middle notes get the largest share because they are the body of the blend, the part you notice most of the time. The base share is small because base oils are strong and slow: use too much and the blend smells heavy from the very start. The top notes are there to make the first few minutes appealing.

Two things bend the ratio in practice:

1. Strength varies. One drop of ylang-ylang, patchouli, clove or peppermint can outweigh three drops of a gentle oil such as sweet orange. A rule of thumb we use: count strong oils as if they were two drops when you plan.
2. Purpose matters. A diffuser blend is smelled for an hour or so, so it can lean on top and middle notes. A skin blend or a personal scent lasts all day and benefits from a firmer base.

Adjust by smell, and write every change down so you can repeat what works.

Building a blend, step by step

This order of work keeps a blend hanging together, whatever oils you start with.

1. Pick the heart. Choose one middle note that matches what you want, such as lavender for an evening blend or rosemary for a desk blend.
2. Add a lift. Choose a top note that shares something with the heart. Bergamot and lavender share a soft, floral side; lemon and rosemary share a clean sharpness.
3. Anchor it. Add one base note to give depth: cedarwood under lavender, frankincense under citrus, vetiver under almost any quiet, settled blend.
4. Look for a bridge. If the top and base seem to argue, a second middle note with something of both can link them. Geranium bridges citrus and woods; clary sage links florals and resins.

Our blend recipes follow this pattern, and every oil profile lists the oils it pairs with most easily.

Testing a blend before you commit

Essential oils are costly and some take a long time to finish, so test small before you mix a full bottle.

• Use scent strips. Put one drop of each oil on its own strip of plain, unscented paper and label the end. Then fan the strips together a few centimeters from your nose. This previews a combination without mixing anything.
• Mix a tiny batch. When you like a combination, mix 5 to 10 drops in a small glass vial, using the ratio you plan to keep. Write the drops down as you go.
• Smell it over time. Dip a fresh strip and smell it straight away, after 15 minutes, after an hour and the next day. A blend that is lovely at first but sour later usually needs more base, or a different one.
• Let it rest. Blends often soften after resting for a day or two in a closed bottle. Judge it again before you make a full batch.
• Patch test the diluted blend. Before using a new skin blend widely, apply a little of the diluted mix to the inside of your forearm. Leave it for 24 hours, or 48 hours if your skin is reactive. Redness, itching or a rash means the blend is not for you. Never test an undiluted blend on skin.

How dilution works

Essential oils are far too concentrated to use neat, meaning undiluted, on skin. For skin use they are mixed into a carrier oil, such as jojoba or sweet almond. Strength is written as a percentage: the share of the finished blend that is essential oil. Our carrier oil comparison covers the carriers themselves.

Drops, milliliters and percentages

A common working figure, and the one our recipes use, is about 20 drops of essential oil per milliliter. Real droppers vary, often between 20 and 40 drops per milliliter, so every drop count is an estimate. If anything, aim slightly under.

Strength	Drops in 10 ml carrier	Drops in 30 ml carrier	Typical use
0.5%	1	3	Face, sensitive skin
1%	2	6	Daily body oil, children over 2, pregnancy
2%	4	12	General adult body and roller blends
3%	6	18	Short-term use on a small area

The Tisserand Institute suggests about 0.5 to 1.2% for facial products and 1 to 3% for body oils and lotions. Higher strengths are for small areas and short periods only. Our adult recipes sit at about 2%. For any bottle size, the dilution calculator works out the drops for you.

A 10 ml (about 1/3 fl oz) roller only takes 4 drops at 2%, which leaves no room for a 30/50/20 split. The fix is to mix a 10-drop concentrate first, in its own labeled glass vial. Then add 4 drops of that mix to 10 ml of carrier.

When an oil has its own limit

The overall percentage is not the only number that matters. Some oils have their own, lower ceiling because they can irritate skin, sensitize it (make it react more each time) or react with sunlight. That ceiling applies to the oil’s own share of the blend, not the total.

• Phototoxic citrus. Cold-pressed bergamot, lime, lemon and grapefruit can cause burn-like reactions on skin exposed to sunlight. Keep each under its limit, or keep the skin covered for 24 hours, as the National Association for Holistic Aromatherapy (NAHA) advises. Steam-distilled lemon and lime, and furocoumarin-free bergamot, do not carry this risk. Furocoumarins are the compounds in pressed citrus oils that cause the sunlight reaction; furocoumarin-free bergamot has them removed.
• Strong sensitizers. Ylang-ylang and lemongrass have very low skin limits under IFRA’s standards for leave-on body products. In a small roller there is no room for even one drop of either, so we keep them for the diffuser.
• Phenol-rich spices. Clove and cinnamon leaf irritate skin and the moist linings of the nose and mouth. One drop in 10 ml is the most either should get, and neither belongs in the bath.

The oil safety lookup lists every oil’s limit in one place.

Children, pregnancy and sensitive skin

NAHA suggests that dilutions for children generally fall between 0.5 and 2.5%, depending on age and purpose. The Tisserand Institute notes that hydrosols (the fragrant water left after distilling an oil) are a gentler option for children under 6. In our recipes, a child over 2 gets half the adult amount.

Some oils, including peppermint, eucalyptus and rosemary, are not for young children’s skin at any strength. Each oil page gives its own age guidance, so check it before you make a blend for a child.

For pregnancy, the International Federation of Professional Aromatherapists recommends 1% or less for skin and no more than 4 drops in a bath. Older adults and anyone with sensitive, broken or inflamed skin also do better at the low end of the range.

Diffusers: a different kind of dose

Percentages do not apply to a diffuser. There, the dose is time and room size. Three to five drops in a typical ultrasonic diffuser is plenty for most rooms, and our diffuser recipes use 4 to 5 drops.

The Tisserand Institute suggests diffusing for 30 to 60 minutes, then pausing for a similar time, with some fresh air coming in. Phototoxicity is not a concern in the air, which is why bergamot and lime appear in our diffuser recipes but not in our rollers.

Pets are a different matter. Before you diffuse anything in a home with animals, read our guide to essential oils and pets.

All 47 oils by note

The chart below lists every oil in our reference as a top, middle or base note. The skin limits are the conservative adult figures we use across this site. “No set limit” means the main safety references give no maximum for that oil. It does not mean the oil can be used neat: normal dilution still applies. The phototoxic column refers to cold-pressed oil on skin that will see the sun.

Oil	Note	Aroma family	Adult skin limit	Phototoxic
Balsam fir	Top	Woody	No set limit	No
Bergamot	Top	Citrus	0.4%	Yes (pressed oil)
Citronella	Top	Citrus	18.2%	No
Eucalyptus	Top	Minty	20%	No
Grapefruit	Top	Citrus	4%	Yes (pressed oil)
Lemon	Top	Citrus	2%	Yes (pressed oil)
Lemon eucalyptus	Top	Citrus	No set limit	No
Lemongrass	Top	Citrus	0.15%	No
Lime	Top	Citrus	0.7%	Yes (pressed oil)
Mandarin	Top	Citrus	No set limit	No
Peppermint	Top	Minty	5.4%	No
Petitgrain	Top	Citrus	No set limit	No
Ravintsara	Top	Minty	No set limit	No
Scots pine	Top	Woody	No set limit	No
Spearmint	Top	Minty	1.7%	No
Sweet basil	Top	Herbaceous	15%	No
Sweet orange	Top	Citrus	No set limit	No
Tea tree	Top	Herbaceous	15%	No
Black pepper	Middle	Spicy	No set limit	No
Cardamom	Middle	Spicy	No set limit	No
Cinnamon leaf	Middle	Spicy	0.6%	No
Clary sage	Middle	Herbaceous	No set limit	No
Clove bud	Middle	Spicy	0.5%	No
Coriander seed	Middle	Spicy	No set limit	No
Cypress	Middle	Woody	No set limit	No
Geranium	Middle	Floral	6%	No
Ginger	Middle	Spicy	No set limit	No
Juniper berry	Middle	Woody	No set limit	No
Lavender	Middle	Floral	No set limit	No
Manuka	Middle	Woody	No set limit	No
Neroli	Middle	Floral	No set limit	No
Niaouli	Middle	Herbaceous	No set limit	No
Nutmeg	Middle	Spicy	0.8%	No
Roman chamomile	Middle	Floral	No set limit	No
Rose otto	Middle	Floral	0.6%	No
Rosemary	Middle	Herbaceous	16.5%	No
Sweet fennel	Middle	Spicy	2.5%	No
Sweet marjoram	Middle	Herbaceous	No set limit	No
Turmeric	Middle	Spicy	No set limit	No
Ylang-ylang	Middle	Floral	0.18%	No
Cedarwood (Virginian)	Base	Woody	No set limit	No
Cistus	Base	Resinous	No set limit	No
Frankincense	Base	Resinous	No set limit	No
Helichrysum	Base	Herbaceous	No set limit	No
Patchouli	Base	Earthy	No set limit	No
Sandalwood	Base	Woody	2%	No
Vetiver	Base	Earthy	15%	No

A high skin limit, such as eucalyptus at 20%, is a ceiling for healthy adults, not a target. For everyday blends, 1 to 2% in total is plenty, and it leaves room for the oils with tight limits of their own.