A Ruler For Windows - is an on-screen pixel ruler, that allows you to perform measurements on your screen. It comes with to skins that resemble a wood ruler and a transparent plastic ruler.
You can customize the length of the ruler, use it vertical or horizontal, and even magnify the screen up to 4x for more accurate measurements. A Ruler for Windows only supports pixel units.
Features
• Each ruler / reading guide can be flipped horizontally or vertically, resized to an exact length or resized by dragging it to a desired length.
• The numbering on the ruler can be reversed and the ruler's length optionally displayed.
• Ticks can be placed on which ever long edge of the ruler you prefer. You can click on a tick to have a measuring line automatically drawn at an exact location.
• Automatic midpoint, third and golden ratio lines can optionally be shown.
• Special 2x, 3x, and 4x modes allow you to take a snapshot of your primary screen and magnify it to more easily measure between very fine points.
Download: 
A.Ruler.For.Windows.3.9.exe - 2.2 MB