The best air purifiers are an excellent tool for eliminating indoor odors and reducing allergens. Simply put, an air filter captures pollutants and expels clean air, much like a tree absorbs carbon dioxide and releases oxygen.

However, just like trees, the types of filters are legion. Carbon pre-filters capture hair and some odors; volatile organic compound (VOC) filters trap odors and airborne pathogens, and HEPA filters reduce indoor allergens such as dust and pollen.