Perfume notes explained: top, heart and base
Notes are not ingredient categories. They describe how fast something leaves your skin — and that one fact explains everything else about the pyramid.
Top, heart and base describe how quickly a material evaporates, not what kind of thing it is. Top notes read for 5–30 minutes and are gone before you have finished a coffee; heart notes carry the working day; base notes are what is still on a scarf a week later. A balanced blend is commonly around 30/50/20 top, heart and base — quoted as shares of the aromatic compound, never of the bottle.
The perfume pyramid is drawn so often, and explained so rarely, that most people assume top, heart and base are categories of ingredient — that citrus is a top note the way a lemon is a fruit. It is not that at all.
A note describes how fast a material evaporates off your skin. Light, volatile molecules leave first and are called top notes. Heavier ones leave last and are called base notes. That is the whole of the classification, and everything else people say about the pyramid follows from it: top notes are bright because light molecules tend to smell that way, base notes are the ones that last because they are physically slower to go.
Two consequences are worth having in mind before you build anything. First, a blend with nothing in the base smells wonderful for an hour and then vanishes — which is what "it doesn't last" almost always means. Second, note proportions are quoted as shares of the aromatic compound and not of the finished bottle, so that diluting a formula to a different strength cannot quietly change the shape of it. The blend view of the dilution tool works this way for the same reason.
The three layers
Weights are for a 10 g compound at the classic 30/50/20 split. The materials named are examples, not a prescription — plenty of things sit between two layers, and lavender is famously in both of the first two.
Splits that work
Front-loaded. Wonderful for the first twenty minutes and noticeably thin after an hour — which is the cologne trade-off, made deliberately. 4.5 g of top material in a 10 g compound, against 1.5 g of base.
The split every book opens with. A bright opening, a body that holds for a few hours and enough base to leave something behind. This is the split to start from if you have no reason to prefer another.
Quiet on application and still there the next morning. The shape most orientals and woods take, and the one that needs the longest maceration. Needs the longest maceration of the three — closer to two months than to 28 days.
What the pyramid actually controls
Almost entirely the base. Top notes read for 5–30 minutes and heart notes for 1–4 hours, so if a blend is all citrus and florals an hour is genuinely all you get. Adding base material is the fix, and it works far better than making the whole thing stronger.
The top notes, and only the top notes — which is why judging a perfume in the shop tells you almost nothing about how you will experience it. It is also why a formula that reads beautifully at ten minutes can be disappointing at four hours, and why the reverse is just as common.
A blend with a gap in the middle drops audibly: the opening leaves and there is a lull before the base arrives. Heart notes are what fill that, which is why the classic split gives them the largest share at 50%. It is also the thing maceration improves most — a blend with rough seams at a week often has none at 28 days.
A base note lasts because it is heavy. A fixative slows down the materials around it, so the whole blend leaves more evenly instead of shedding its top notes and stalling. Iso E Super is the usual workhorse at about 10% of the compound — nearly odourless at low loads, and it pushes everything near it forward. Some people cannot smell it at all, which is worth finding out before you build a formula on it.
A group of materials blended so they read as one smell rather than as their parts — the perfumery equivalent of a chord. A fougère accord is lavender, oakmoss and coumarin doing something none of them does alone. Accords are built and tested on their own, then used in a formula as though they were a single material, which is why perfumers talk about them as ingredients.
Building a blend that behaves
One top, one heart, one base at 30/50/20 teaches you more than a ten-material formula. You can smell what each is doing, and when something is wrong you know which row to change.
Dip a strip, label it, and come back to it at an hour, four hours and the next morning. That is the only way to see the shape of a blend, and it costs you nothing but patience. Skin is the final test and a poor first one — it varies hour to hour.
Making a weak-lasting perfume stronger gives you a louder version of something that still disappears at the same time. Adding base notes or a fixative changes when it disappears, which is what the complaint is actually about.
Iso E Super and Benzoin resinoid and most absolutes are strong enough that a whole trial can be lost to one careless drop. Working from a 10% dilution makes small amounts measurable and mistakes recoverable.
Check the split as you build
The blend view shows what your compound is actually running at against the split you picked — so a formula that will not last is obvious before you wait a month for it.
Open the dilution tool →Print the note pyramid
Top, middle and base splits with the percentages that actually work. One page, free.
Estimates, not advice. Every figure on this page is computed from published reference values and standard measures, so your own inputs, equipment and conditions will move it. Nothing here is professional advice — talk to a qualified professional before acting on it.