The ingredient list on the back of a jar is written in INCI — the International Nomenclature of Cosmetic Ingredients — a standardised naming system used worldwide. It looks impenetrable, but it follows a few rules that make it far more useful than the marketing copy on the front.
Order tells you concentration
Ingredients are listed in descending order by weight, down to one percent. After that threshold, the manufacturer can list them in any order. So if the ingredient you are paying for appears after the preservatives and fragrance, you are looking at a very small amount of it.
The first five do most of the work
They typically make up the large majority of the formula. Water, a humectant such as glycerin, an emollient, an emulsifier, and a thickener — that is a moisturiser. The interesting actives usually sit lower down.
Latin names are plants
Botanical ingredients carry their botanical binomial, often with the common name in brackets. Butyrospermum parkii is shea butter. Simmondsia chinensis is jojoba. It looks clinical, but it is simply the standard.
What the list cannot tell you
It will not tell you the exact percentage of an active, the pH of the formula, or how the ingredients behave together — all of which matter. A well-formulated product with a modest concentration frequently outperforms a poorly buffered one with an impressive number on the label.
Read the list to rule things out — a known irritant, an allergen you react to — rather than to rank products against each other.