Reader question: How do I know if my skin is oily, dry, or combination? Indicators? - @allison.j.yood I’ve talked about the best moisturizers for combination skin, and that brought me to another more simple—but essential—skincare question from a reader: how to know what type of skin you have. Although it’s impossible to categorize something as nuanced as your skin into a singular class, it does serve as a good baseline when looking for skincare products. “Skin type is primarily determined by genetics,” says Hadley King, MD, a board-certified dermatologist in New York City. “That being said, it can also be influenced by medications, particularly hormonal and cholesterol-lowering medications. Topical products should also be taken into account—for example, if you used topical retinoids regularly, this may make your skin more sensitive.” And yes, skin type can change with age. As we get older, our skin gets drier since it goes through significant hormonal shifts. It’s also possible to develop sensitivity over time, so don’t assume that your skin type today will be the same skin type 10 years from now. It’s important to consistently pay attention to your skin in order to understand where it’s at and how it evolves. Now, for the nitty gritty—here’s a basic breakdown of each skin type. However, it’s important to note that dryness and dehydration aren’t quite the same thing. To put things simply, dryness refers to a skin type, and dehydration refers to a skin condition. Dry skin is a result of a lack of oil in the skin, while dehydrated skin is the result of a lack of water in the skin. People with dehydrated skin don’t necessarily have dry skin—it could be oily, combination, or normal skin that is simply lacking hydration. Apply two clean blotting sheets on different parts of your face: one on your forehead, and one on your cheeks. Afterward, hold the sheets up to the light to see how much oil was absorbed. The more oil there is on the paper, the more likely you have oily skin. If there is little to no oil visible on either sheet, you have drier skin. And if the blotting sheets reveal drastically different levels of oil, your skin is probably combination. Keep in mind that you can have more than one skin type. In fact, it’s likely. For example, someone with sensitive skin can be dry or oily. This is when things get a bit more complicated, so I’ve included a more comprehensive test below. If you find that two or more points in any one of the categories describe you, then go for the products labeled for that skin type(s). From there, you can build a personalized routine with products that work best.

Choose Products for Oily Skin If:

By mid-afternoon, a greasy film has developed on your face, even though your skin felt fine when you left home this morning.The culprit? You probably have an oily T-zone.Acne breakouts are making you feel like your 16-year-old self.(Minus the homework and boy-band crushes.)The more you scrub your skin, the oilier it seems to get, and the more you seem to break out.That’s because stripping the skin of oils prompts it to produce even more oil to compensate and restore balance.

Choose Products for Dry Skin If:

Patches of skin on your face or body are flaky, whatever the season.Or if you find that “winter skin” never seems to disappear. Your complexion appears dull and lackluster, no matter how many “brightening” products you apply.The reason? Dry skin doesn’t reflect light as well as hydrated skin. Moisturizer doesn’t really make a difference, no matter how thick and creamy it is or how much you apply.This happens when the moisturizer can’t penetrate the scaly skin barrier.

Choose Products for Sensitive Skin If:

Regular beauty products leave your skin irritated, red, and sometimes stinging.Scented products can be especially troublesome.Changing the kind of laundry detergent you use sets off a rash on your finicky skin.Even using a new towel can make you see red.Some spa treatments, such as intensive facials and alpha hydroxy peels, feel too strong.You would much prefer a massage to having someone pick and poke at your face.

Choose Products for Combination Skin If:

Your forehead is typically shiny, while appearing dry or normal on the cheeks.Oil patrol for your T-zone is necessary. You tend to break out in the same areas.Most likely, it will be the aforementioned oily parts. Different skincare products work in some areas but irritate others.You might be tempted to mix and match products instead of using an all-in-one moisturizer.

Choose Products for Normal Skin If:

Forgetting to bring a cleanser on a trip is no problem since you can just use the one at the hotel.Did I mention how lucky you are?In your makeup routine, setting sprays and mattifying powders don’t really seem necessary.Seriously, you’re so lucky.You’re able to tolerate higher levels of typically irritating ingredients, such as retinol or glycolic acid.Go thank your parents right now.