Active ingredients are formulated into a variety of beauty products—from cleansers to creams to serums. You can find them at many price points, too; they are also both OTC or prescription-strength. However: How the active is formulated, to what percentage, and how high quality the ingredients are can make a pretty big difference in the outcome. So while actives can be found in a wide range of products, they are certainly not all created equal.

The most potent, of course, are prescriptions to be given by a dermatologist. These—like retinols, azelaic acid, benzoyl peroxide, and others—are formulated at such percentages that they should be monitored by professionals and given to those who need them. If you feel your skin concern warrants a derm's visit, you'll most likely be given one.

OTC options run the gamut. You can find serums and creams north of $500 at retailers or direct-to-consumer—or you can find drugstore options that are decidedly less costly. The type of product, too, tends to have an influence. For example, face washes are often less expensive than serums or creams, so even if your cleanser has an active in it, it may be less costly than its cream counterpart.

Essentially: When you're dealing with OTC products, what to look for is entirely up to you, your preferences, and cost limitations. If you can only afford options at your drugstore? Don't worry, there are plenty of good choices that will help your skin (Alba Botanicals and Burt's Bees are two favorites.) Or if you'd like to spend more, you can look to department stores or retailers like Sephora or Credo for additional options—these more expensive options may have stronger actives or simply more actives in the formula.

What are "inactives"?

So, unless you're just using a pure ingredient—there's likely going to be other additives in the formula which are not considered "actives." And while you may be tempted to think that these are nothing more than filler, many times they serve a purpose.

There are preservatives—in the natural space, look for phenoxyethanol, sea salt, and citric acid, among others—which keep the formula free of mold and bacteria for long-term use. They can also help stabilize the product so you can keep it around for more than its typical shelf life.

Or there are ingredients that help improve absorption, like propanediol, which helps deliver the actives and enhances the sensorial experience.

Finally, there are the more recognizable options that serve as your bases—things like botanical oils, shea butter, aloe, and so on—so you have a well-rounded product.

The takeaway.

Understanding skin care can sometimes feel like alchemy. Just when you figure out how to decode an ingredient label, you now have to figure out how those ingredients play together—and which one is doing the heavy lifting. That's essentially what you're doing when you dive into actives. But once you're better aware of what we mean when we talk about the concept, you'll be better able to decipher your skin care routine.