How to start a perfume formula from an idea

Start a perfume formula by writing the idea as one sentence, building the accord that carries that sentence, and only then laying a skeleton of three lines around it and dosing each line by its role. Weighing comes last, and the first version should be small enough to disagree with.

How do I write the brief?

One sentence, with a subject and a mood, and no material names. "Cold rain on warm stone." "A lemon tart cooling on a window sill." "Someone's old leather jacket in a pine wood." If you cannot say the idea without naming a material, you have a material you like, not an idea, and the formula will end up being that material with company.

The sentence is a test you will use for weeks. Every version gets held up to it: does this smell like the sentence? A version that smells good and does not smell like the sentence is a different perfume, and you are allowed to keep it, but you should notice.

Why build the accord first?

The brief usually contains one image that is doing most of the work, and that image is an accord: three to five materials that together say one thing. Build it on its own, on strips, before it meets anything else. If the accord does not say "warm stone" alone, no amount of top and base will make it say so later.

Keep the accord at 100 percent within itself and settle its internal ratios first. It then goes into the formula as one line at one dose, which means later versions can move it up or down without opening it up again.

What is the three-line skeleton?

The first full version of a perfume needs only three jobs filled:

1. The accord you just built. It is the heart, and it carries the idea.
2. One opening line that speaks in the first ten minutes and points at the idea. Not a second idea; an introduction to the first.
3. One base line that is still on the strip the next morning and agrees with the accord.

That is the whole skeleton. It will sound thin, and it is meant to; a skeleton that already sounds finished has nowhere for the next ten versions to go. Every later addition has to earn its place by doing a job none of these three does.

How do I dose by role?

Dose is set by what a line is for, then corrected by how loud the material is. As a starting shape for the concentrate, before any trial:

• Opening: a fifth to a third of the concentrate. Citrus oils and light aromatics take the upper end; a strong aldehyde takes a small fraction of a percent.
• Heart, including the accord: a third to a half.
• Base: a quarter to a third. A powerful musk or amber at a few percent can be the whole base.

Then look at the material's impact. A quiet material at 30 percent and a loud one at 0.5 percent can be equally audible. The catalog's impact figure on every material page tells you which end of its range a material starts at, and the ratio is what you tune, never the absolute gram.

A worked example

Brief: "Cold rain on warm stone."

The accord is the stone: mineral, dry, faintly warm. Three lines: Iso E Super 60 parts for the dry woody body, Vetiveryl acetate 25 for the earthy edge, Ambroxan 15 for the warmth that stays. Trialled on strips for two days; the ratios hold, so the accord is frozen.

The skeleton around it. Opening, the rain: Helional, a watery green aldehyde, at 6 percent of the concentrate, with Bergamot Essential Oil at 14 percent so the rain has light in it. Heart: the stone accord at 55 percent. Base: Cashmeran at 10 percent, warm and slightly musky, to agree with the Ambroxan already inside the accord, and Galaxolide at 15 percent to carry it into the next morning. That is 100 percent in five lines, one of which is an accord of three. Dilute to 15 percent in ethanol, strip it at 10 minutes, one hour and the next day, and hold it against the sentence.

What should I not do in version one?

• Do not add a material "to be safe". If it has no job you can name, it is noise.
• Do not chase the finished perfume. Version one is a question, and its answer is version two.
• Do not weigh before the ratios are settled. Parts on paper cost nothing; grams of absolute do.
• Do not skip writing the brief down. The sentence is what stops the formula wandering.

PerfuMate lets you write the brief and ask the AI for a first skeleton built only from materials on your own shelf, capped at the number of lines you set; the AI is handed the catalog and your shelf on every run and is never trained on them. The scent profile shows the opening, heart and base shares of each version, and the evolution tree keeps version one where you can come back to it. See AI Studio or see how the bench works.