An odometer or odograph is an instrument used for measuring the distance traveled by a vehicle, such as a bicycle or car. The device may be electronic, mechanical, or a combination of the two (electromechanical). The noun derives from ancient Greek ὁδόμετρον, hodómetron, from ὁδός, hodós and μέτρον, métron ("measure"). Early forms of the odometer existed in the ancient Greco-Roman world as well as in ancient China. In countries using Imperial units or US customary units it is sometimes called a mileometer or milometer, the former name especially being prevalent in the United Kingdom and among members of the Commonwealth.

पथमापी एक उपकरण है जो किसी वाहन द्वारा चली गयी दूरी मापने के लिए प्रयुक्त होता है। यह इलेक्ट्रॉनिक, यांत्रिक या दोनों का सम्मिलित प्रणाली हो सकती है।