Abstract: An auxiliary footrest for removably mounting to a chair having a post is disclosed. The footrest includes a clamp configured to be removably mounted to the post of the chair and generally C-shaped frame fixed to the clamp. The frame includes a foot support bar and opposite ends which define respective mounting rods for mounting the frame to clamp. The clamp includes a first bracket and a second bracket, each of which may be generally W shaped. Each of the brackets is mounted between the respective mounting rods of the frame, receiving the post between opposed V-shaped wall sections of the brackets. The brackets are secured to exert a squeezing force against generally opposite sides of the post, thereby fixing the footrest to the chair so that the foot support bar is cantilevered forwardly and elevated above the floor. The user can install and/or adjust the footrest at a desired vertical level for custom comfort.