zzRuler : Free On-Screen Ruler App for Windows

zzRuler is a basic portable ruler app for Windows. When launched it shows a regular ruler on your screen. Both of the sides of these ruler are marked to measure lengths in the terms of centimeters.

As we double-click on zzRuler.exe in order to launch zzRuler, it immediately shows a ruler on your computer screen. The rules is yellow colored and has some level of transparency to it. This transparency enables us to see through the ruler so that we can measure objects much more accurately. We can drag this ruler anywhere on the screen for measuring various things.

Change ruler orientation

zzRuler is initially shown in the horizontal orientation, but we can change its orientation to vertical simply by right-clicking on it and then choosing Toggle Orientation. We can also use the hotkey Ctrl+O to switch the orientation of this on-screen ruler between vertical and horizontal. Using the ruler in these two different orientations can be useful when measuring varying objects being displayed on the screen.


Units for measurement

By default, zzRuler uses the centimeter unit for the measurement. The markings for cm are displayed on both the edges of the ruler. But we can change the units for measurement from the settings of zzRuler. We can choose the units like pixels and inches.

Custom background color

As we can see that the zzRuler app uses a gradient of two yellow shades for the background color. But from the settings, we can change these two colors and make zzRuler appear in any color gradient of our choice. If you do not like the gradient effect, then you can choose both background colors to be the same color.

Adjust ruler opacity

Among other things, we can choose the font face, font size and also the text-color for the markings on the ruler. We can also control the opacity level for the ruler. If you are wondering about how to close this ruler and make it disappear, then you can use the hotkey Ctrl+F4 to close this app.


zzRuler can come handy when we want to measure the length and width of a window or other items. We can use it to measure objects in pixels, cm or inches.

You can download zzRuler from https://drive.google.com/.