Makeup base, also referred to as a primer, is a cosmetic product that is applied to the skin before foundation or concealer. It is typically simply a clear, matte finish or a very light tint. Its purpose is to smooth out lines, wrinkles, or blemishes, and give the foundation or concealer a smooth palette for application. It also helps to absorb oil, and cuts down on shine throughout the day, which can help the makeup last longer. A makeup base is typically oil free, and may include some moisturizing ingredients as well, to condition the skin even as it serves as a base for makeup.
For some people with relatively smooth skin, makeup base might be unnecessary to achieve a smooth look with foundation and concealer. Experts generally recommend only using the makeup products that are needed, because too much makeup can potentially clog the pores. For people who have wrinkles they want to cover up, or significant redness or blemishes on the face, applying a makeup base can provide a smooth canvas to make it easier to cover these things up. In stores, it is typically located near the foundation and concealer products, and is comparably priced to these items.
A makeup base is intended to be applied after a daily moisturizer onto clean, dry skin. It should generally just be smoothed over the face, and it will dry to a matte finish. Liquid or powder concealer may then be applied over the makeup base to cover up any remaining areas of redness, followed by liquid or powder foundation to finish the look. This makeup primer might have a slight tint, but generally these products do not have color so they do not interact with the color of the foundation, and make it look too dark.
This product may also be referred to as a photo primer or makeup primer, because it can help to give skin that smooth, airbrushed look that is often desired in professional photography. Because it is intended to absorb oil and shine, it can also make other types of makeup last longer throughout the day without needing to be reapplied. Makeup base is typically intended to be noncomedogenic so it won't clog the pores, and it may also include certain moisturizing ingredients to treat the skin; however, it is still important to wash all the makeup off the face at the end of the day to prevent blemishes.