There are several differences between foundation and concealer, most particularly in usage. Depending on the variety, the colors of foundation and concealer may also vary. The overall pigmentation and consistency of these two types of makeup is also different, as is the packaging.
Both types of makeup are meant to create the image of a flawless complexion. Foundation, however, is applied all over the face in a tone that matches the skin exactly. While it can cover minor spots, it typically is not meant for correcting severe discoloration, very noticeable scaring, or acne.
Concealer is meant to be applied sparingly directly over blemishes or flaws to hide them; it is essentially meant to cover up things that a foundation cannot. Depending on one’s skin type, both foundation and concealer can be used together or alone. Concealer is not supposed to be applied all over the face in the same way as foundation.
The color of the makeup also varies. Foundation typically comes in a range of different flesh tone colors. While it can come in cooler or warmer tones for minor color correction, it is still meant to blend invisibly into the skin. While concealer also comes in a variety of skin colors, it also available in bases of red, pink, blue, and green. These specialized concealers help to cancel out opposite tones in the skin. If a foundation came in these colors, it would typically create a rather unnatural finished look; as concealer is only applied to tiny parts of the face, however it can still look natural.
Another one of the primary differences between foundation and concealer is the pigmentation of the two products. The former is typically less pigmented than the latter. Even when the two products are the same shade, layers upon layers of foundation would be needed to achieve the same color payoff as one layer of concealer.
Both foundation and concealer can come in liquid, cream, or powder form. When in the same form, however, concealer is significantly thicker than foundation. As foundation is meant for the entire face, it needs to be easily bendable. Concealer only needs to be able to blend slightly in a small area during application; therefore it is usually noticeably thicker.
Foundation comes in a tube, bottle, compact, or a tin with loose powder. In most instances, only one shade of foundation is included in each of these. Concealer, however, typically comes in a stick, pen, small tin, or palette. In higher end stores, concealer is usually sold with several different shades and color correcting pigments in one package, thereby providing an all-in-one product for various areas of the face and significantly more options than a single foundation.