Abstract: An adjustable wrench has a body, a movable jaw, a pinion, a sliding rack and a positioning device. The pinion is rotatably mounted between and engages the movable jaw and the sliding rack. The pinion longitudinally extends or retracts the movable jaw quickly when the sliding rack is moved. Moreover, the positioning device locks the sliding rack in position to keep the movable jaw stable in use.

Abstract: An adjustable wrench has a body, a movable jaw, a pinion assembly, a sliding rack and a positioning device. The pinion assembly has a first pinion corresponding to and engaging the sliding rack and a second pinion engaging the first pinion and the movable jaw. Thereby, the pinion assembly transversely extends or retracts the movable jaw quickly when the sliding rack is moved longitudinally. Moreover, the positioning device locks the sliding rack in position to keep the movable jaw stable during use.