Brown and gray match and are suitable for use with one another. Gray is considered neutral as are black and white. Because gray is neutral, it theoretically is paired appropriately with any color on the color wheel, including brown.
Although not neutral in the technical sense of the word, artisans, designers, decorators and others often refer to brown as a "neutral color." In fact, brown is suitable for use with a broad range of hues appearing on the color spectrum. This includes cooler colors, such as blues and greens, as well as hotter colors, such as reds, oranges and yellows. Different shades of brown typically complement and harmonize well with each other.