Perfect Screen Ruler is the only name that would be suggested to you if you are looking to measure the size of any object on the screen.
    Measure any item on the screen with accuracy and perfection, this easy to use tool utility and its features will help you in doing so. The tool is capable in measuring almost any item on the screen, whether it is the size of a button or the distance between two points. At times the utility can also enlarge the images. With an easily apprehendable interface the tool allows to; activate the required window, activate the utility, get the screenshot of the object, uses the left mouse button in marking measurement points, connecting these points and the measurable area is more visible, connect points together with a line and enclosed into a rectangle, vertical and horizontal distance between these two points are displayed in pixels and can be measured with ease.
    The tool also supports a screen map that allows in easily reaching to the selected area with ease.