The manner in which the abrasive grains are distributed on the backing is referred to as its "Coating". The two levels of abrasive grain density are Open Coat and Closed Coat.

Abrasive grains cover approximately 50% - 60% of the coated surface. Open Coat products generally offer greater flexibility, faster cutting, and provide a greater resistance to loading. Open Coat products used widely for woodworking applications.

Abrasive grains cover 100% of the coated surface. The greater number of abrasive grains normally results in a higher amount of stock removal during the useful life of the product. Closed Coat products are widely used in metalworking and some woodworking applications.