Ingredient lists can feel like a wall of Latin and chemistry. This is a plain-language primer to about sixty of the most common names you'll see on a skincare label — grouped by the job they do in the bottle, described honestly. Every entry tells you what the ingredient's role is in the formula, not what it will do to your skin, because that part depends on the whole product, the amount used, and you.
How to read an ingredient list
Not medical advice — talk to your clinician.
Cosmetic labels use INCI names — a standardized naming system so the same ingredient reads the same way on a bottle in Sydney, London, or New York. That's why you'll see "Aqua" for water and long botanical Latin names for plant extracts.
Ingredients are generally listed from most to least, by amount — until you reach the ones present under about one percent, which can appear in any order (colorants are often bunched at the very end). So the first few names usually tell you the bulk of what's in the jar.
Every note below describes a role — humectant, emollient, surfactant, and so on — meaning the job the ingredient does inside the formula. It is not a claim about results. Think of it as reading the recipe, not the review.
Humectants — the water-binders
Humectants attract water and hold it in the upper layers of a formula (and the skin surface), which is why they turn up in almost every serum and moisturizer.
Glycerin — A humectant that binds water and leaves a softer after-feel; one of the most-used ingredients in all of skincare.
Sodium Hyaluronate / Hyaluronic Acid — A strongly water-binding ingredient used to hold water within a formula; the sodium salt form is more stable and the one you'll usually see.
Butylene Glycol — A lightweight humectant that also acts as a solvent, helping other ingredients dissolve evenly.
Propanediol — A plant-derived humectant and solvent used as a lighter-feeling alternative to older glycols.
Sodium PCA — A humectant related to compounds found in skin's own surface moisture, used to bind water in a formula.
Urea — A humectant used to bind water and soften the feel of a product.
Panthenol (provitamin B5) — A water-binding ingredient that also adds a smooth, cushioned slip.
Betaine — A gentle sugar-beet-derived humectant used to bind water.
Emollients, oils and occlusives — feel and barrier
Emollients and oils add slip, cushion and a smoother surface feel. Occlusives go a step further and form a barrier-style layer that slows water evaporating from the surface. Silicones are a smooth-feeling sub-family often used for spreadability.
Squalane — A lightweight emollient (a stable version of squalene) that adds slip and a non-greasy finish.
Caprylic/Capric Triglyceride — A silky emollient derived from coconut and glycerin, used to spread a formula evenly.
Cetearyl Alcohol — A fatty alcohol (not the drying kind) used as an emollient and to give creams body.
Cetyl Alcohol — A fatty alcohol used as an emollient and to thicken lotions and creams.
Butyrospermum Parkii (Shea) Butter — A rich plant butter used as an emollient for cushion and a protective after-feel.
Adansonia Digitata (Baobab) Seed Oil — A plant oil used as an emollient for slip and product feel.
Aleurites Moluccanus (Kukui) Seed Oil — A light plant oil used as an emollient.
Ceramides (e.g. Ceramide NP) — Lipid-type ingredients similar to those found between skin cells, used to build a barrier-style feel in moisturizers.
Dimethicone — A silicone that spreads easily for a smooth, slip-y finish and a soft-focus surface feel.
Petrolatum — An occlusive that forms a cushioning barrier layer to slow water loss from the surface.
Tocopheryl Acetate — An oil-soluble, stable form of vitamin E used to condition the feel of a formula.
Allantoin — A conditioning agent often included for a soothing, calming label story.
Surfactants — the cleansers
Surfactants are the workhorses of anything that foams or rinses. They loosen oils and soils so water can carry them away. They range from strong and high-foaming to very mild.
You'll often see two or three paired together — a main cleanser plus milder "co-surfactants" that soften the overall feel.
Sodium Laureth Sulfate — A high-foaming surfactant that lifts oils so they rinse away; milder-feeling than its "lauryl" relative.
Sodium Lauryl Sulfate — A strong, high-foaming surfactant.
Cocamidopropyl Betaine — A mild coconut-derived co-surfactant used to boost foam and soften harsher cleansers.
Coco-Glucoside — A gentle sugar-derived surfactant that foams lightly.
Decyl Glucoside — A gentle sugar-derived surfactant common in "mild"-positioned cleansers.
Sodium Lauroyl Methyl Isethionate — A mild surfactant used in creamy, low-foam cleansers and syndet bars.
Sodium Lauroyl Glutamate — An amino-acid-derived surfactant used in gentle, lower-pH cleansers.
Sodium Chloride — Ordinary salt, used here to thicken and adjust the consistency of surfactant-based cleansers.
Preservatives, emulsifiers and texture agents
Any formula that contains water needs a preservative system, or it spoils. Emulsifiers keep oil and water phases blended, and thickeners give a product its gel or lotion body — the quiet infrastructure behind how something looks and pours.
Phenoxyethanol — A broad-use preservative that protects a water-containing formula from microbial growth.
Ethylhexylglycerin — A preservative-booster and conditioning agent often paired with phenoxyethanol.
Potassium Sorbate — A food-grade preservative often used in gentler and natural-leaning formulas.
Sodium Benzoate — A food-grade preservative used to protect formulas, frequently alongside potassium sorbate.
1,2-Hexanediol — A multi-tasking preservative that also behaves like a humectant-solvent.
Xanthan Gum — A natural thickener used to give gels and lotions their body.
Carbomer — A synthetic thickener used to build clear, wobbly gels.
Glyceryl Stearate — An emulsifier that keeps oil and water evenly blended in a cream.
Cetearyl Glucoside — A sugar-derived emulsifier used to hold an emulsion together.
Citric Acid — A pH adjuster used to fine-tune a formula's acidity.
Disodium EDTA — A chelator that ties up trace metals so preservatives and textures stay stable.
Tocopherol (vitamin E) — An antioxidant used mainly to keep a formula's oils from going off.
UV filters
UV filters are the ingredients that scatter or absorb ultraviolet light in sun-care products. Mineral filters sit largely on the surface; organic (chemical) filters absorb specific bands of UV.
Honest limit: which filters are allowed, and at what levels, differs a lot by country. In the United States, sunscreen filters are regulated as over-the-counter drugs by the FDA; in the EU, Australia and much of the world they're regulated as cosmetics. An SPF number belongs to the finished, tested product — not to any single filter — so you won't find SPF figures in an ingredient dictionary.
Zinc Oxide — A mineral UV filter used in sun-care formulas where local rules allow.
Titanium Dioxide — A mineral UV filter that doubles as a white colorant.
Butyl Methoxydibenzoylmethane (Avobenzone) — An organic filter that absorbs UVA light.
Octocrylene — An organic filter often included to help stabilize other filters.
Homosalate — An organic filter that absorbs UVB light.
Ethylhexyl Methoxycinnamate (Octinoxate) — A widely used organic UVB filter.
Actives, antioxidants and exfoliating acids
"Actives" is a loose marketing word for ingredients a formula is often built around. Below, the notes stick to what each one is and how it behaves in a formula — whether it's water- or oil-soluble, how stable it is — not what it will do for your skin. That last part is genuinely individual, and for anything medical it's a conversation for a clinician.
Exfoliating acids are grouped by chemistry: AHAs are water-soluble, BHA is oil-soluble.
Niacinamide — A water-soluble form of vitamin B3 that dissolves into the water phase of leave-on formulas.
Retinol — A vitamin-A derivative that is unstable in light and air, so it's usually sold in opaque, air-tight packaging.
Bakuchiol — A plant-derived, oil-soluble ingredient used in leave-on formulas, often in "gentle"-positioned products.
Ascorbic Acid (vitamin C) — A water-soluble antioxidant that is famously unstable; formulas keep it fresh with low pH and air-tight packaging.
Magnesium Ascorbyl Phosphate — A more stable, water-soluble vitamin-C derivative used as an alternative to pure ascorbic acid.
Salicylic Acid — A beta-hydroxy acid (BHA); oil-soluble, so it turns up in cleansers, toners and leave-on serums.
Glycolic Acid — The smallest alpha-hydroxy acid (AHA); water-soluble and used at low pH.
Lactic Acid — An AHA that also behaves as a humectant, giving it a gentler feel than glycolic.
Mandelic Acid — A larger-molecule AHA that works more slowly than glycolic.
Azelaic Acid — A dicarboxylic acid used in leave-on formulas.
Centella Asiatica Extract — A botanical extract used for a soothing, "cica"-style label story.
Adenosine — A conditioning ingredient used in leave-on formulas.
Caffeine — Often used in eye-area products for a temporary tightened surface feel.
Aloe Barbadensis Leaf Juice — A plant-derived, water-based ingredient used for a cooling, botanical formula character.
Fragrance, "allergens," and what Komplexion adds
You'll sometimes see names like Limonene, Linalool, Citronellol or Benzyl Alcohol near the end of a list, tagged in some markets as fragrance allergens. That label isn't a danger warning — under EU rules, certain fragrance components must be named individually so anyone who reacts to them can spot them. It's transparency, so you can make your own call.
This primer is a curated slice — about sixty universal names to make a label less intimidating. It deliberately doesn't score anything or tell you what's "good" or "bad" for you, because that depends on the whole product and on your own skin.
Komplexion is a private companion skincare app that scans the ingredient list on a product you actually own and shows the role of each name against its full library. The full library lives in the app; this page is the friendly front door to it.
INCI stands for the International Nomenclature of Cosmetic Ingredients — a standardized naming system so the same ingredient reads the same on labels around the world. It's why water shows up as "Aqua" and plants appear under their Latin names.
Are ingredients really listed in order of how much is in the product?
Generally, yes — highest amount to lowest — until you reach ingredients present under about one percent, which can be listed in any order. Colorants are often grouped at the very end regardless of amount.
Does "fragrance allergen" mean an ingredient is harmful?
No. In the EU, certain fragrance components must be named on the label so people who react to them can identify them. It's a transparency rule, not a warning that the ingredient is harmful for everyone.
Do these notes tell me what an ingredient will do for my skin?
On purpose, no. Each note describes the ingredient's job inside the formula — humectant, emollient, preservative, and so on. How your skin actually responds depends on the finished product, the concentration, and you. This isn't medical advice — for anything medical, talk to your clinician or dermatologist.
Why isn't there an SPF number next to the UV filters?
SPF is a property of the finished, tested product, not of any single filter — and which filters are allowed differs by country. An ingredient dictionary can tell you a filter's role, but not a sunscreen's rating.
Is this the whole Komplexion ingredient library?
No — this is a hand-picked primer of around sixty common names. The full library lives inside the Komplexion app, which scans the ingredient list on a product you own and shows each ingredient's role.