The finger-mounted mechanical counter is a numerical counter that may be worn on the finger of a user. First, second and third wheels each have a set of indicia formed thereon, each set of indicia being a circumferentially arrayed set of integers, such as a continuous range from 0 to 9. The first, second and third wheels are rotatably mounted within a housing having corresponding first, second and third slots formed therein for display of the corresponding indicia. The housing defines a central passage which is adapted for receiving the finger of the user. After a full rotation of the first wheel, the second wheel is rotated by a single increment, and after full rotation of the second wheel, the third wheel is rotated by a single increment, allowing for consecutive counting from single digits to double digits to triple digits.