Range finder for determining the distance between the user and an object of known height or width, such as a golf flagstick, structure, etc. The range finder is a flat card, having a series of graduated apertures, each aperture being dimensioned to correspond to a particular distance to the flagstick. Range information is provided for each aperture. The user holds the card 24 inches from the eye and sights the flagstick through the apertures. The range information for the aperture whose diameter most closely corresponds to the height of the sighted flagstick is the actual distance between the user and the flagstick. The apertures are graduated in size, to represent range information in specific increments. The size of the increments is selected to facilitate optimal performance and may vary within a series of apertures.