How to Read Skincare Ingredient Labels: INCI Lists, Fragrance and What to Avoid

To read a skincare ingredient label, start with the order: ingredients are listed in descending order of predominance, from most to least, but anything at 1% or less can appear in any order and colorants go at the end. Then find the active ingredient, check for "fragrance" or "parfum", and look for anything your skin has reacted to before. The claims on the front tell you much less.

Below we cover what an INCI list is, how US and EU labeling rules differ, what the first five ingredients do and don't tell you, what "fragrance" can hide, which ingredients have real evidence against them, what words like "hypoallergenic" and "clean" mean legally, and how to test a product before it goes on your face.

What is an INCI list?

An INCI list is the ingredient list on a cosmetic, written with standardized names so the same substance has the same name on every product. INCI stands for International Nomenclature of Cosmetic Ingredients, and the Personal Care Products Council is the organization behind the INCI naming system. In the US, FDA rules require ingredients to be named using names adopted in references such as the CTFA Cosmetic Ingredient Dictionary where they exist, and the European Commission's CosIng database lets you look up an ingredient's INCI name; it describes itself as a non-legally binding information database.

In practice, that's why labels look strange. Water often appears as "Aqua (Water)", plant extracts use Latin botanical names, and familiar vitamins go by chemical names: vitamin E is listed as tocopherol and vitamin B3 as niacinamide. Once you know a handful of these, most lists get much easier to scan.

What order are skincare ingredients listed in?

In both the US and the EU, ingredients run from the largest amount to the smallest, down to about 1%. Below that line, brands can list ingredients in any order. The US and EU rules differ on the details:

The US rules come from the FDA's Cosmetics Labeling Guide, and the EU rules from Article 19 of the EU Cosmetics Regulation, which also requires nanomaterials to be marked "[nano]". Makeup sold in many shades can also carry a "may contain" or "+/-" list of colorants that covers the whole range.

What do the first five ingredients mean?

The first five ingredients are the largest parts of the formula, so they tell you what the product is mostly made of: usually water, a solvent, oils or emollients, and humectants that hold water. That makes them a good guide to texture and to the overall type of product. If you have dry skin and the top of the list is water and alcohol, you're looking at a light formula.

They tell you less than people expect, for three reasons:

• No percentages. The label shows order only. The fifth ingredient could make up 10% of the formula or 2%.
• No visible 1% line. Below 1%, order is free, so an ingredient near the end could be present at 0.9% or at a trace. Small amounts can still matter: a thickener like xanthan gum is typically used at about 0.1 to 0.5%, according to the formulator-run site INKEEDecoder.
• Position isn't risk. An ingredient's place on the list doesn't predict how the finished product behaves on your skin. Researchers testing finished cosmetics found that products made with comedogenic ingredients are not necessarily comedogenic, because old ingredient-by-ingredient ratings came largely from animal models.

Where do I find the active ingredient?

On US products that are also drugs, such as sunscreens, the active ingredients are listed first, under the heading "Active Ingredients", followed by the rest as "Cosmetic Ingredients" or "Other Ingredients". That box tells you which UV filters are doing the work. For how much to use once you've found the right one, see how much sunscreen to use on your face.

For ordinary cosmetics there is no separate active box. A serum sold on niacinamide or retinol lists it in the main list like any other ingredient, so its position is the only clue to the amount unless the brand states a percentage on the pack.

What does "fragrance" on an ingredient list mean?

"Fragrance" (or "parfum" in the EU) is a single word that can stand for a mixture of many ingredients. Under US rules, fragrance ingredients can be listed simply as "Fragrance", and the FDA notes that fragrance formulas are the kind of components most likely to be treated as trade secrets. The FDA also says it does not have the same legal authority to require allergen labeling for cosmetics as for food. The 2022 MoCRA law requires the FDA to set fragrance allergen labeling rules, but they weren't on labels yet when we wrote this.

The EU goes further. Listed fragrance allergens must be named in the ingredient list when they exceed 0.001% in leave-on products or 0.01% in rinse-off products, which is why EU labels often show names like linalool, limonene or benzyl alcohol after "parfum". Regulation (EU) 2023/1545 added 56 more fragrance allergens to that requirement: from 31 July 2026 non-compliant products can no longer be placed on the EU market, and older stock can be sold until 31 July 2028.

Why it matters: fragrance allergy affects around 1% of adults, and DermNet ranks it second only to nickel as a cause of allergic contact dermatitis. Two traps are worth knowing:

• "Unscented" is not "fragrance-free". The FDA warns that unscented products can still contain fragrance added to mask the smell of other ingredients. If fragrance bothers your skin, choose products labeled fragrance-free and still check the list.
• Botanicals can be fragrance too. DermNet notes that words like "botanical", "herbal" or "natural" may signal an unidentified fragrance. In a study of 1,470 products sold as "clean", 82.9% contained fragrances or botanicals, with linalool in 20.7% and limonene in 19.0%.

Which skincare ingredients should you avoid?

Avoid the ingredients your own skin has reacted to, plus a short list with strong evidence or legal problems behind it. Most viral "toxic ingredient" lists go much further than the evidence does.

• Methylisothiazolinone: after an epidemic of allergic contact dermatitis in Europe, authorities banned MI in leave-on cosmetics in 2017 and limited it in rinse-off products in 2018. In five Belgian hospitals, the share of patients sensitized fell from 7.9% in 2014 to 3.1% in 2019.
• Mercury: the FDA lists the names it may hide under, mercurous chloride, calomel, mercuric, mercurio or Hg, and advises avoiding products with handmade labels, labels not in English, or no label at all.
• Hydroquinone: the FDA says there are no FDA-approved or legally marketed OTC skin lightening products. The FDA recommends talking with a doctor about treating dark spots. Our guide to fading dark spots covers over-the-counter options.

Also check whether ingredients clash when you layer products. Our guide to skincare ingredients not to mix covers the common pairs.

What do "hypoallergenic", "organic" and "clean" mean on a label?

Legally, very little. The FDA says there are no federal standards or definitions for "hypoallergenic"; the term means whatever a particular company wants it to mean, and companies don't have to submit evidence for it. "Organic" is not defined in the laws FDA enforces for cosmetics, although the USDA's National Organic Program does define it for agricultural ingredients. "Clean" has no standard, scientific basis or regulatory oversight, and in the study above most "clean" products contained at least one potential allergen. Read the ingredient list instead.

How do I test a new product before using it on my face?

Do an at-home use test on a small patch of skin for 7 to 10 days. The AAD's steps:

1. Choose a quarter-sized spot where the product won't be rubbed or washed off, such as the inner forearm or the bend of the elbow.
2. Apply the product twice a day for seven to 10 days, in the amount you would normally use.
3. Leave it on as long as you normally would. For a rinse-off product like a cleanser, leave it for five minutes or as long as the instructions say.
4. If your skin reacts, wash it off gently and don't use it again. If there's no reaction after 7 to 10 days, you can start using it.

If you keep reacting and can't tell to what, a dermatologist can do patch testing, which involves placing small amounts of allergens on the skin under cover for 48 hours and checking again a few days later. For a gentle routine while you sort it out, see our sensitive skin routine.

Can an app read an ingredient label for you?

Yes, and it saves time when a list runs to 40 names. Pori has an ingredient scanner (part of Pro, on iPhone): scan a product's barcode or photograph its ingredient label, and each ingredient is flagged beneficial, use with caution or avoid for your skin type. The ratings come from fixed rules over a curated list of about 250 common INCI ingredients; the AI only reads hard-to-read labels and writes a short summary of a verdict that has already been computed. Barcode lookup uses Pori's own catalogue plus Open Beauty Facts data, so US coverage is thinner than in the biggest databases, and photographing the label fills the gap. We compare Pori with other tools in our roundup of skincare ingredient checker apps.

An app is not a diagnosis. It can't tell you whether you're allergic to an ingredient; only your own reaction, or patch testing by a dermatologist, can.