How to Blend Essential Oils: Notes, Ratios and a Draft Log

The top, middle and base labels describe how fast materials leave the skin or a blotter, not how many drops of each belong in a bottle. Use the pyramid as planning vocabulary, then judge every blend by smelling it at set intervals, changing one thing per draft, and writing down what you smell. This guide covers where the pyramid comes from, why ratio rules like 30/50/20 break down, a draft-by-draft method with worked arithmetic, and the usual reasons a blend fails.

Amyris Essential Oil bottle

Amyris Essential Oil

Our own Amyris Essential Oil, in sizes from 0.5 oz to bulk.

From $20.99

Shop Now →

What the pyramid actually measures

A 2021 chemical-engineering review by Rodrigues, Nogueira and Faria in Molecules uses Jean Carles' pyramid and attaches skin durations to it: top notes, typically citrus, last about 15 to 30 minutes; middle notes (spice, leather, floral) about 3 to 4 hours; base notes, typically amber or musk, more than 4 hours. Those durations are a teaching scale. The same paper models evaporation with Raoult's law adjusted by an activity coefficient: the vapor a material gives off depends on its vapor pressure, its share of the mixture and how it interacts with its neighbours. A label on a bottle is not in that equation. A material's behavior in your blend is.

Steffen Arctander, in his 1960 Perfume and Flavor Materials of Natural Origin, did not use a pyramid. He described three stages when an oil is studied on a blotter: the topnote (the first impression, sometimes very brief), the body-note (the main odor, with a much longer life) and the dry-out, which he says shows the tenacity of the material. His examples make the point that lasting power and pleasantness are separate: lemon oil has a fresh topnote, a body-note that may last one or two hours on a blotter, and "no Tenacity"; patchouli oil, by contrast, he reports staying perceptible on a blotter "for weeks or months."

The practical consequence is that the pyramid has three limits you should plan around. It ranks materials by fade rate, so it says nothing about strength. It describes single materials, while a blend changes the rates (see the fixation section below). And it describes a blotter or a skin surface at a moment, not a bottle. J. Stephan Jellinek, writing in the 1960 paper "Evaporation and the Odor Quality of Perfumes", cautioned that a material which slows evaporation on a paper blotter is not necessarily doing so on skin, in a cream or in a spray, "since the conditions of evaporation are different in all of these cases."

Why 30/50/20 does not settle anything

A 30/50/20 split (top/middle/base) circulates widely as a rule of thumb. We could not trace it to a perfumery text we could open, so we treat it as a convention, not a finding. Reasoning from the sources above, three things make any fixed ratio unreliable. First, drops are not equal strengths: Arctander notes that patchouli's sweetness is "almost sickening in high concentration," so a base oil of that kind at 20% of a blend can swamp everything above it. Second, a very quiet base can sit at 40% and barely register. Third, the labels are not fixed: Arctander's note on patchouli and vetiver is that they show no typical dry-out within the same day and need "at least 24 hours of study," so a blotter check after ten minutes tells you nothing about the base.

If you want a ratio to start from, use one as a first draft and expect to move it. Fix the total essential-oil percentage first (that is a safety decision, covered below), then split that total between roles.

Build one change at a time

The method below is our editorial recommendation, reasoned from the evaporation sources above: change one variable at a time so each result has one cause. We have not trialled it.

  1. Define the job. A diffuser blend, a body oil and a perfume applied to skin each evaporate under different conditions. Jellinek's point about blotter versus skin applies in both directions: a blend that smells right on paper has not yet been proven on skin.
  2. Pick the base first. The base is the material whose behavior you most need to control, and it is the slowest to evaluate. Decide what you want the dry-out to be, then choose upward from there.
  3. Add the middle, then the top, one material at a time. After each addition, smell before adding the next.
  4. Change one variable per draft. Either a material or its share, never both. If draft 4 is worse than draft 3, you know which change did it.
  5. Write it down. Draw a table with these columns: draft number, formula in parts, the single change from the previous draft, smell at first sniff, after 30 minutes, after 3 hours, the next day, and a verdict. The columns follow Arctander's topnote, body-note and dry-out stages; the "next day" column is there because of his 24-hour caution for tenacious materials.
  6. Keep conditions constant. Arctander stresses a constant room temperature and humidity when judging oils on blotters, because both change how an odor reads. Evaluate in the same room, away from cooking and other scents.

A worked example with amyris as the base

Suppose the goal is a body oil with a woody-citrus character, for skin, in a 10 mL bottle. The arithmetic below starts from the total dose and then divides it. The carrier oil is not something we sell; any reputable supplier will do.

Worked arithmetic for a 10 mL body oil at 2% total essential oil
StepCalculationResult
Total essential oil10 mL x 2%0.2 mL
Draft 1, equal roles (1:1:1)0.2 mL / 3About 0.067 mL each of base, middle and top
Draft 2, change only the base share (2:1:1)0.2 mL x 2/4, then 0.2 mL x 1/4 twice0.10 mL base, 0.05 mL middle, 0.05 mL top
Carrier to make up10 mL minus 0.2 mL9.8 mL

For turning those milliliters into drops, see our essential oil dilution chart; drop size varies enough between droppers that weighing or measuring in mL is more reliable. The 2% ceiling is the upper end of the 0.5% to 2% range we give for our own amyris oil on skin, so the same total works as a cap for the whole blend while you are learning.

What amyris contributes in that base is worth stating carefully. Our own description is creamy, woody, balsamic with a soft vanilla undertone. Arctander described amyris oil in 1960 as "faintly woody, not dry," with a "very tenacious" body odor that "rapidly loses the rich, complex odor, fading out in a very weak, woody-balsamic note," and he added that the odor varies "depending on the age of the oil and the age of the wood prior to distillation." He called it a "mild blender," and judged its woody effect "far inferior" to that of sandalwood oil. Reasoning from that: amyris is a quiet base that supports and rounds a blend. It is a poor choice if you expect the base to supply a distinct dry-out character on its own. Smell your lot before committing, and see our posts on blending amyris with citrus, spice and floral oils and amyris in perfumery for pairings.

One number worth having: a supplier data sheet from De Hekserij (2025) for its Haitian amyris oil lists a boiling point of 288 degrees C and a vapor pressure of 1.5 Pa. Read as a single figure for a mixture of many compounds, it is indicative of a low-volatility material, which is consistent with a base position, but it is not a measured wear time.

Reading a blotter without fooling yourself

Arctander's method is the simplest to adopt. Dip a blotter in each draft, label it, and return at the intervals in your table. Note three things: what you smell first, what the main character is once the first impression fades, and what is left. He describes the dry-out as appearing "after one hour, several hours, or perhaps not until the next day," and as the stage that "often reveals adulteration" and the effect of fixing components. Two practical refinements follow from the sources. Give each draft its own labeled blotter, and keep your skin test as a separate, later step. Skin is the only test that matters for something you will wear, and a patch test comes before it: see our patch test guide.

Fixation: why a blend can change on the way down

Jellinek defined fixation as a material's slower evaporation caused by adding another substance, and he warned against calling anything "a fixative" unless its action has been shown in the setting where it is used; he reports that one proposed explanation is simply that the added material dilutes the odorant and lowers its partial vapor pressure. Arctander, describing the high-boiling "so-called fixatives," says that in a way they "steal" effect from the perfume. Reasoning from both, adding a heavy base to a bright citrus blend can mute the opening, and that is a trade-off to expect, not a defect in your blend. Our guide to natural perfume fixatives goes further, and our base note essential oils list and woody essential oils compared cover the materials themselves.

Dilution, IFRA and the limit of what we can tell you

The dose comes before the artistry. Our shop guidance for amyris on skin is a dilution of 0.5% to 2% in a carrier oil, patch tested first, kept away from eyes, children and pets, and not taken internally. The De Hekserij sheet applies the IFRA Standards (51st Amendment) to its amyris oil and lists maximum levels in finished products: 0% for products applied to the lips, and 10% for categories that include products applied to the face and body with fingertips and fine fragrances, with the supplier adding that it advises lower amounts in specific cases. Those figures are industry safety ceilings for professionally formulated products, not recommendations for a home blend. Where our 2% and a published 10% differ, we recommend the lower figure, especially for sensitive uses such as the face.

Every other oil in a blend has its own limits, which we cannot list for oils we do not sell. Check each supplier's safety data sheet, and ask a pharmacist or dermatologist if you have skin conditions, take medication, or are pregnant (ask an OB-GYN or midwife). If you intend to sell a blend, labeling and safety-assessment duties are a regulatory matter for a cosmetic regulatory specialist. For how essential oils and synthetic fragrance materials differ in what a label implies, see essential oil versus fragrance oil.

When a blend fails: find the cause, then change one thing

What these sources cannot tell you

Arctander wrote in 1960 about industrial perfumery materials, some of which are no longer used, and the Rodrigues review concedes that vapor-liquid equilibrium calculations alone do not describe the "Aura of Aroma" accurately. We are a one-oil shop with no perfumer on staff, and the arithmetic above is a starting method worked out from dilution percentages, not a set of trialled recipes. Treat it as a way to structure your own smelling, not as a guarantee about how a given blend will wear.

A good blend is mostly a record of decisions: a total dose you chose for the use, a base you understand, and drafts that each changed one thing. If you keep that log, the pyramid stops being a rule and becomes what it is, a shorthand for what you wrote down at the 30-minute and next-day marks.

Amyris Essential Oil bottle

Amyris Essential Oil

Amyris Essential Oil from our own shop, in sizes from 0.5 oz to bulk.

From $20.99

Shop Now →

Sources & Further Reading