A nail clipper includes a clipper body with a pair of jaws, an operating lever configured to move the jaws to cut nails, a hook member mounted to the clipper body, the hook member including a vertical groove portion extending vertically downwardly from an upper surface of the hook member, and first and second lateral groove portions extending in lateral direction from the vertical groove. The operating lever includes a front tip portion of generally bar or shaft shape, which is configured to be inserted through the vertical groove portion of the hook member and to couple with a selected one of the first and second lateral groove portions of the hook member to set a desired gap size of the matching jaw portions of the clipper body.