Short answer
To read a perfume formula written by someone else, first work out its unit — grams, percent, parts or parts per thousand — and whether the numbers include the solvent of diluted materials. Then decode each line's dilution notation ("10% DPG", "@1%", "1% sol."), expand the abbreviations, identify any premixes or bases, and convert the whole thing into grams for the batch you want to make. Before weighing anything, check that the total makes sense, that every material is one you can identify exactly, and that the formula has been checked against the restrictions for your product.
Step 1: what are the numbers?
| Written as | Means | Clue |
|---|---|---|
| Grams | Weights for one specific batch | Total is a batch size (10 g, 100 g); often a "g" after numbers |
| Percent | Share of the formula by weight | Total is 100 |
| Parts per thousand | Share out of 1,000 | Total is 1,000; "ppt" or "‰" |
| Parts | Relative amounts with no fixed total | Total is arbitrary (87, 243) |
| Drops or ml | Volume-based amounts | Small whole numbers; unreliable — convert by weight |
Parts and parts per thousand convert to percent by dividing each line by the total; parts per thousand in perfume formulas shows how. Volume and drops need densities and are best re-made by weight; see perfume weight vs volume.
Step 2: decode dilution notation
Most formulas weigh some materials as solutions. Common notations, all meaning the same kind of thing:
- "Ambroxide 10% DPG — 20": 20 units of a 10% solution of ambroxide in DPG. It contains 2 units of ambroxide.
- "Indole @1%" or "Indole 1% sol.": a 1% solution; the solvent may not be named.
- "Indole 0.2 (as 1%)": ambiguous — is 0.2 the weight of solution or of indole? Find out from context or the author before weighing.
The biggest reading error is mixing these up. Decide, line by line, whether the number is the weight of solution or of pure material, and write it out explicitly. The reason it matters is the difference between a row's weight and its pure active, explained in formula %, absolute % and relative %.
Step 3: expand abbreviations
| Abbreviation | Usually means |
|---|---|
| DPG, IPM, TEC, BB, DEP | Solvents: dipropylene glycol, isopropyl myristate, triethyl citrate, benzyl benzoate, diethyl phthalate |
| EO, abs., res., CO₂ | Essential oil, absolute, resinoid, CO₂ extract |
| PEA | Phenylethyl alcohol |
| MDJ | Methyl dihydrojasmonate (sold as Hedione and similar) |
| HCA | Hexyl cinnamal (hexyl cinnamic aldehyde) |
| C-10, C-12 MNA, etc. | Aliphatic aldehydes by carbon number; MNA is methyl nonyl acetaldehyde |
| "50 IPM", "50 BB" | A material supplied at 50% in that solvent |
Trade names (Iso E Super, Galaxolide, Hedione) are brand names of specific materials, sometimes with close equivalents sold under other names by other makers — which may or may not smell identical. Identify each material precisely, preferably with a CAS number; see fragrance material names and CAS numbers.
Step 4: find the premixes
Lines such as "rose base", "musk accord" or a proprietary base name are premixes. If the author gives their composition, you can make them; if not, you need the same commercial base or a substitute, and the result will differ. How premixes enter a formula's arithmetic is in how to calculate a premix inside a formula.
Step 5: convert to grams and check
- Write the formula out again in your own template, one material per line, with pure material and solvent explicit.
- Convert to percent, then to grams for your batch size.
- Check the total, and check that every line can be weighed accurately on your balance; make dilutions where it cannot.
- Check restricted materials at the concentration and in the product category you intend; a published formula has not been checked for your product. Use how to calculate IFRA compliance.
- Record where the formula came from, and every assumption you made in reading it.
Red flags
- Totals that are nearly but not exactly round (98.7, 1,013) — often a transcription slip.
- Materials named only by odor ("musk", "amber") with no identification.
- No dilution shown for materials that are almost never used neat.
- Volumes or drops for powerful materials.
- No date, version or source — you cannot know if it is the version the author approved.
The arithmetic of turning any formula into a weighed batch is collected in the perfume dilution and calculations guide, and how formulas fit into the craft overall is in the perfume formulation guide.
Frequently asked questions
Is it worth making published formulas?
As exercises, yes — reading and making someone else's formula teaches notation and structure. Treat them as unverified: many published formulas are untested or incomplete, and none have been assessed for your product.
Why do some formulas not add up to 100?
They may be in parts, or deliberately leave the solvent out, or contain a transcription error. Work out which before weighing.
Written and reviewed by the RUŌOD Lab team. This article is general education about perfume formulation and record-keeping; it is not legal, regulatory or safety advice, and the examples are illustrations, not validated commercial formulas. How we write and check these guides.