Frequently asked questions

The upper bound is set by the fragrance oil's IFRA limit and you need to stay under it. Conventional ranges are around 3 to 8 percent for cologne, 8 to 15 percent for EDT, 15 to 22 percent for EDP and 22 to 30 percent for parfum. If the limit does not allow it, staying lower is correct rather than forcing those ranges.

Working at 25 percent by volume, a 50 millilitre bottle needs 12.5 millilitres of fragrance oil and 37.5 millilitres of base. If you weigh in grams, the oil's density of roughly 0.95 g/ml means 12.5 millilitres corresponds to about 11.9 grams. At 20 percent the same bottle uses 10 millilitres of oil.

In a volumetric calculation the percentage is read in millilitres; in a gravimetric one it is read in grams. Because the components have different densities, the same percentage corresponds to different amounts in the two methods. Professional perfumery works by weight as standard; volumetric work is also common at home.

With an average density of 0.95 g/ml, 1 gram of fragrance oil is about 1.05 millilitres and 1 millilitre is about 0.95 grams. The conversion is millilitres equals grams divided by 0.95. On that basis 10 grams is 10.53 millilitres, 50 grams is 52.63 millilitres and 100 grams is 105.26 millilitres. Real density varies between 0.85 and 1.05 g/ml depending on the composition.

The defaults are 0.95 g/ml for fragrance oil, 0.79 g/ml for a premixed base, 0.789 g/ml for alcohol, 1.0 g/ml for distilled water and 1.03 g/ml for fixative. You can change the density of every component in the calculator.

Yes. The reverse calculation takes the amount of oil you have and your target concentration, then shows the total blend volume, how many bottles it makes and what is left over. For example, 50 millilitres of oil at 25 percent gives 200 millilitres of blend — exactly four 50 millilitre bottles.

Yes. You set the alcohol, distilled water and fixative shares yourself; in the calculator you can add extra components such as Hedion or Iso E Super and enter a percentage and density for each.

In its shortest form, four steps: decide the concentration (staying under the fragrance oil's IFRA limit, typically in the 18 to 30 percent range), work out the oil and base quantities for your bottle volume, add the oil first and then the base and mix, then leave it to macerate somewhere dark and cool. Example: a 50 millilitre bottle at 25 percent by volume uses 12.5 millilitres of oil and 37.5 millilitres of base. The base can be a premixed perfume base or an alcohol, water and fixative blend you build yourself.

Essentially fragrance oil, a base (a premixed base or perfumer's alcohol), a precise scale reading to 0.01 grams, syringes or pipettes, dark glass bottles and labels. Do not use plastic containers; fragrance oil at high concentration affects plastic over time.

Perfume uses pure ethanol, that is, denatured perfumer's alcohol. Pharmacy ethyl alcohol is usually 70 percent, so it contains water and will not give the same result. Methylated spirits must never be used, as they can contain methanol.

No. An essential oil is a single-source material obtained from a plant by distillation or expression; a fragrance oil is a composition a perfumer built from dozens of natural and synthetic raw materials in a deliberate structure. Dilute a fragrance oil and you get a perfume; dilute essential oils and you get a mixture of raw materials.

The blend has not finished macerating. In the first days the sharp top note of the alcohol dominates; after two to four weeks resting somewhere dark and cool that note recedes and the composition settles.

One to two weeks is reasonable for light citrus blends, two to four weeks for floral and fruity ones, and four to eight weeks for woody and resinous compositions. You only find the exact time by smelling it periodically and taking notes.

There are three common reasons: the concentration is too low, the blend has not rested long enough, and there is no heavy component holding the bottom of the composition. A fixative, a woody floor such as Iso E Super, or resinous materials like benzoin and vetiver improve longevity noticeably.

IFRA is the industry standard that sets safe use levels for fragrance raw materials. The limit states the maximum concentration of a fragrance oil in the finished product applied to skin, and it differs for every oil, because the figure is set by the most restricted raw material inside that oil.

Ask your supplier for an IFRA Conformity Certificate. The document contains a table of maximum use levels category by category; leave-on products applied to skin, such as perfume and cologne, fall into category 4.

You enter the limit into the fragrance oil's record once, it stays in front of you on the calculation screen, and you get a warning when the concentration goes above it. But the accuracy of that limit and the final decision belong to the maker; Esansmatik does not perform a safety assessment.

The real risk is not a single exposure but a cumulative one: skin sensitisation can appear months later as redness, itching or lasting sensitivity. Some citrus components can also cause pigmentation under sunlight.

Placing a product on the market as a cosmetic brings legal obligations such as a product information file, a safety assessment and label declarations. Esansmatik does not cover those processes; if you are considering commercial sale you need to consult the applicable regulations and a specialist.