Why do some oils keep your skin glowing, while others clog pores and trigger breakouts?
Some ingredients sink beautifully into your facial skin, while others may contribute to the formation of comedones and acne. The difference often comes down to the comedogenic rating.
This comedogenicity scale empowers you to see which oils and cosmetic ingredients are more likely to clog pores — and which are considered non-comedogenic and least likely to cause acne. While it’s not a perfect science, understanding the comedogenic scale gives you a simple tool to take control of your skincare routine and avoid pore-clogging ingredients that may interfere with your skin health.
Think of it less as a rulebook and more as a roadmap: a way to navigate natural ingredients and choose what works best for your unique skin type. With the right knowledge, you can balance the beneficial properties of oils, avoid highly comedogenic ingredients, and create skin care products that hydrate, protect, and support your skin barrier.
👉 Let’s break down what this scale really means — and how you can use it to choose better skincare ingredients for your routine.
What Does Comedogenic Rating Mean?
The word comedogenic comes from “comedones,” the tiny bumps that appear when pores get clogged with excess sebum, dead skin cells, or certain ingredients. When an oil or cosmetic ingredient is labeled comedogenic, it simply means it has a higher likelihood of clogging pores and may contribute to acne breakouts.
On the flip side, non-comedogenic ingredients are considered least likely to cause acne. But it’s important to note that this isn’t an absolute truth. Your skin type, genetics, and even the overall formulation of a skincare product all influence how your skin responds. This means that the effectiveness of the comedogenic scale is directly tied to your unique skin type, making it crucial to understand and consider when choosing skincare products.
So, when you see “non-comedogenic” printed on a jar, think of it as a guide — not a guarantee. Understanding the comedogenic scale helps you avoid problematic ingredients, but the real secret is learning to observe how your skin reacts over time. Your active participation in observing your skin’s response is key to a successful skincare routine.
👉 Next, let’s look at the comedogenic rating scale itself and what a rating of 0 to 5 really means.
The Comedogenic Rating Scale (0–5 Explained)
To make things easier, cosmetic chemist James Fulton developed the comedogenicity scale — a rating system that scores oils and ingredients from 0 to 5 based on their likelihood of clogging pores.
- Rating of 0 → least likely to clog pores, considered non-comedogenic (e.g., hemp seed oil, argan oil).
- 0–1 → very low risk, often safe for acne-prone skin.
- 2–3 → moderately comedogenic, may cause breakouts depending on skin type and formulation.
- Rating of 4 → high comedogenic risk, more likely to cause acne in prone skin (e.g., coconut oil, shea butter).
- 5 → highly comedogenic ingredients, almost certain to clog pores (e.g., cocoa butter, wheat germ oil).
Here’s a quick list of comedogenic ingredients by rating:
- Low (0–1): grapeseed oil, sunflower oil, rosehip oil
- Moderate (2–3): almond oil, avocado oil, sesame oil
- High (4–5): coconut oil, cocoa butter, wheat germ oil
It’s important to note that this scale is based on the Fulton rabbit ear model and doesn’t always reflect how human facial skin responds. Still, it remains a helpful starting point when scanning an ingredient list or building a DIY formula.
👉 Next, let’s explore the real-life factors that influence comedogenicity — beyond just the numbers.
Factors That Influence Comedogenicity
The comedogenic rating of an oil or cosmetic ingredient doesn’t exist in a vacuum. Even a rating of 4 doesn’t automatically mean it will clog your pores — context matters. Here are the main factors that shape the real impact on your skin.
Individual Skin Variability
Every skin type is unique. Genetics, sebum production, and barrier health all influence whether a certain ingredient will trigger acne or not. An oil that’s considered high comedogenic for one person may feel perfectly safe on another’s acne-prone skin. This is why it’s important to observe how your skin responds instead of relying only on numbers.
Concentration & Formulation
The likelihood of clogging pores increases when an oil is used at 100% concentration. However, the same oil may behave differently when diluted in a balanced formulation — for example, blended into a moisturizer or serum with humectants and antioxidants. The overall formulation, not just the comedogenic rating, determines how a skincare product performs.
Sunlight & Oxidation
Some oils oxidize quickly when exposed to heat, light, or air. Once oxidized, they may contribute to pore-clogging or even irritate sensitive skin. For example, cocoa butter is naturally rich and protective, but if poorly stored, it can turn rancid and become problematic. Adding natural antioxidants or storing oils in dark glass helps protect their beneficial properties and reduce the risk of breakouts.
👉 Now that we’ve seen how skin type, concentration, and stability affect comedogenicity, let’s look at some common pore-clogging ingredients to watch for.
Pore Clogging Ingredients to Watch For Skincare
While the comedogenic rating is a helpful guide, some ingredients are consistently flagged as more likely to clog pores — especially when used in high concentrations or on acne-prone skin. Here are a few to keep an eye on:
- Coconut oil → Often given a rating of 4, this oil is rich in fatty acids but may cause acne breakouts in those prone to clogged pores.
- Cocoa butter → Luxuriously moisturizing and protective, yet considered a high comedogenic ingredient that can be problematic for oily or acne-prone skin.
- Isopropyl myristate → A synthetic emollient used in many cosmetic care products. It gives a silky feel but is among the most pore-clogging ingredients.
- Beeswax → A natural occlusive that locks in moisture and protects, but in some formulations, it may contribute to clogged pores if used heavily.
It’s important to note that none of these ingredients are inherently “bad.” They all have beneficial properties and play useful roles in skincare products. The key is to know your skin type and use them in the right context and concentration.
👉 Next, let’s compare two key fatty acids — linoleic and oleic — and see how their balance shapes whether an oil is acne-friendly or more likely to cause breakouts.
Fatty Acids and Oils: Linoleic vs Oleic Acid
Behind every comedogenic rating lies the chemistry of fatty acids. The balance of linoleic and oleic acid in an oil often determines whether it’s acne-friendly or more likely to clog pores.
Linoleic Acid Oils → Light and Acne-Friendly
Oils high in linoleic acid tend to be lighter, faster-absorbing, and least likely to cause acne. They help rebalance sebum in acne-prone skin and support the protective barrier. Popular choices include rosehip seed oil, grapeseed oil, and hemp seed oil. These are considered non-comedogenic or very low on the scale, making them ideal for facial skin.
👉 Learn more in my Botanical Oil Guide.
Oleic Acid Oils → Nourishing but Risky
Oils rich in oleic acid are thicker, more occlusive, and deeply moisturizing. Olive oil and avocado oil are classic examples. They’re soothing for dry skin and have antiinflammatory properties, but they are moderately comedogenic and may contribute to breakouts if overused on acne-prone skin.
👉 Curious about oil stability? Check out my post on the Iodine Number in Cosmetics to understand how fatty acids impact oxidation and skin care formulations.
How Comedogenic Ratings Are Tested (and Why They’re Not Absolute)
Most of what we know about the comedogenic rating comes from the Fulton rabbit ear model, first published in 1982 (Fulton, 1982 – PubMed). In these tests, ingredients were applied to the inner ear of a rabbit, and researchers observed whether comedones developed. The results were then used to assign ratings on the 0–5 scale.
While groundbreaking at the time, this method has major limitations. Rabbit skin is thinner, more sensitive, and not identical to human facial skin. An oil that is highly comedogenic on a rabbit may not cause acne on a person — and vice versa.
It’s important to note that modern cosmetic testing now uses alternative methods, but the Fulton scale remains the most widely cited reference. For formulators and DIY enthusiasts, the key takeaway is simple: treat the comedogenic scale as a guideline, not a fixed rule. Always patch test, use one new product at a time, and observe how your skin responds.
👉 Next, let’s look at some of the best oils and butters by skin type — so you can match your choices to your own unique skin needs.
Best Oils & Butters by Skin Type
Not every oil with a moderate or even high comedogenic rating will spell disaster for your skin. The key is matching the right ingredients to your skin type and using them in balanced formulations.
Acne-Prone Skin
If you struggle with breakouts, look for oils that are least likely to clog pores. Jojoba oil is considered non-comedogenic and closely mimics the skin’s natural sebum. Grapeseed oil and hemp seed oil, both high in linoleic acid, are lightweight and acne-friendly. These oils provide hydration without increasing the likelihood of clogging pores. Explore the full Botanical Oil List for more acne-safe choices.
Dry Skin
When your skin feels tight, flaky, or dull, richer oils and butters can act as protective occlusives. Olive oil, avocado oil, and even cocoa butter deliver deep moisture and barrier support. While cocoa butter carries a high comedogenic rating, in small amounts within a balanced formulation it can help hydrate and protect dry skin. Learn more in my Ultimate Guide to Botanical Butters.
Sensitive Skin
For delicate, easily irritated complexions, choose gentle, soothing oils with antiinflammatory properties. Sweet almond oil is nourishing yet mild, while babassu oil and meadowfoam seed oil are light, stable options that rarely cause breakouts. These are considered non-comedogenic and well tolerated even on sensitive facial skin. For more inspiration, check out my DIY Skincare Ingredients hub.
👉 Next, let’s see how to actually use comedogenic ratings in your daily skincare routine — from reading labels to balancing ingredients.
How to Use Comedogenic Ratings in Your Skincare Routine
Knowing the comedogenic rating of an oil or butter is useful — but the real magic happens when you apply that knowledge to your everyday skincare routine. Here’s how to make the scale work for you:
Step 1: Read ingredient labels carefully.
When scanning a skincare product, look beyond the marketing claims. If coconut oil or cocoa butter appear high on the ingredient list, remember they carry a higher likelihood of clogging pores.
Step 2: Patch test before full use.
Your unique skin may respond differently than the scale predicts. Apply one new product at a time on a small area and observe how your skin responds over a few days.
Step 3: Balance humectants and occlusives.
A formula rich in occlusive, comedogenic oils can sometimes cause acne. Pairing them with humectants like glycerin helps hydrate without overwhelming your skin. This balance is key to barrier health and overall skin care.
Step 4: Don’t demonize all oils.
It’s important to note that even a high comedogenic ingredient may perform beautifully in the right context. A rating of 4 doesn’t automatically mean it will cause acne; it may depend on the concentration and the overall formulation.
👉 Want to see how this looks in practice? Browse my DIY Skincare Recipes for acne-safe formulations you can try at home.
FAQs: Understanding the Comedogenic Scale
What is the highest comedogenic rating?
The comedogenic scale goes from 0 to 5. A rating of 5 means the ingredient is highly comedogenic and very likely to clog pores. Examples include cocoa butter and wheat germ oil. These are usually avoided in acne-prone skin, though they can still be beneficial in small amounts for dry skin.
Which oils have a comedogenic rating of 0?
Oils with a rating of 0 are considered non-comedogenic and least likely to cause breakouts. Jojoba oil, argan oil, hemp seed oil, and squalane are good examples. They’re ideal for acne-prone and sensitive skin, making them some of the safest skincare ingredients. See the full Botanical Oil List for more.
What is the comedogenic rating of coconut oil?
Coconut oil usually has a rating of 4, which makes it a high comedogenic ingredient and likely to clog pores in acne-prone skin. While it has protective and antibacterial properties, it may contribute to breakouts when used on the face. Learn more in my Botanical Oil Guide.
How accurate are comedogenic ratings?
It’s important to note that comedogenic ratings are guidelines, not absolute truths. They’re based on the Fulton rabbit ear model (Fulton, 1982 – PubMed), which doesn’t always reflect how human skin responds. Your skin type, concentration in the formula, and overall formulation all matter. Always patch test and use one new product at a time.
What is the comedogenic rating of shea butter?
Shea butter has a rating of 4, but it behaves differently depending on the formulation and skin type. On dry skin, its occlusive, protective qualities help lock in moisture. On acne-prone skin, however, it may cause breakouts. For a deeper dive, read my Ultimate Guide to Botanical Butters.
👉 Finally, let’s wrap this up with why the comedogenic scale should be seen as a tool, not a strict rule.
Final Thoughts: A Tool, Not a Rule
The comedogenic rating is a helpful guide — but it’s not a final verdict on whether an oil or ingredient will clog your pores. Skin is personal. What may trigger acne in one person might provide protective, moisturizing benefits in another.
It’s important to note that your unique skin and the overall formulation matter just as much as the number on the scale. That’s why the best approach is to patch test, introduce one new product at a time, and observe how your skin responds.
Think of the comedogenicity scale as a tool: a way to narrow down your choices, avoid problematic ingredients, and build a skincare routine that feels safe, sustainable, and tailored to you.
👉 Explore more in my DIY Skincare Ingredients guide.
👉 Get inspired by DIY Skincare Recipes designed with acne-prone skin in mind.
👉 Learn how to make every choice planet-friendly with Sustainable Beauty Practices.
Here’s to creating skin care products that support your skin health and respect the planet — one ingredient at a time. 💚
Warmly,
Kristina
