An arrow rest cord length and lock adjustment device is disclosed. An example device includes a body having a plate section between a first end portion and a second end portion. A plurality of openings are formed in the body. A cord is threaded through the openings so that when the cord is under tension and fixed at one end of the body, one of the openings applies an orthogonal torquing force about an axis of another of the openings which in turn imparts a binding effect on the cord. At least one detent is provided on the body. An o-ring is received in the at least one detent and provided over a portion of the cord and a portion of a perimeter of the body to bring the cord closer to the plate section of the body.