How to read a cosmetic ingredient list
Most packs in Europe, the UK and the United States print ingredients in a block headed "Ingredients" (or "Ingrédients"). The names follow the International Nomenclature of Cosmetic Ingredients, known as INCI. A single material should have the same INCI name from one brand to another, even if the marketing name on the front of the pack changes.
Order on the list
In the EU, the UK and the US, ingredients are generally listed in descending order by concentration. Ingredients present at 1 percent or less may be listed in any order at the end. Colourants often appear at the very end, sometimes as CI numbers (for example CI 77491 for red iron oxide).
Water, parfum and CI numbers
Water is usually first, under the name Aqua or Water. Parfum or Fragrance is a single word that can stand for a mixture. In the EU and the UK, a set of well-known fragrance allergens must be named separately when they exceed a legal threshold; those names (linalool, limonene, citral and others) then appear in addition to Parfum. CI numbers are colour index numbers for pigments.
What the list will not tell you
The list will not tell you the exact percentage of each ingredient, the grade or particle size, or, in many cases, whether a material is plant-derived, palm-derived, fermented or synthetic. Claims such as "natural" or "clean" are marketing language and are not a substitute for the INCI list. "Unscented" is not the same as "fragrance-free".
This page is a reading guide, not legal advice. Rules are more detailed than a short article can be, and they differ by country and by product type (a sunscreen, for example, may be a cosmetic in one place and a drug in another).