A convertible sit-to-stand desk has a desktop that is manually movable into and between a lowered position and a raised position, a base that is configured to support the desktop with respect to a supporting surface, and a supporting frame that supports the desktop with respect to the base. The supporting frame facilitates movement of the desktop into and between the lowered and raised positions. The supporting frame comprises first and second sub-frame assemblies disposed on opposite sides of the desktop, respectively.