Have a ruler on your screen any time, any where, with the push of hotkeys. Works great with other apps. This is a must-have tool for graphic design or picture editing.

Premium features include:
- Easy switching between units (pixel, inch, cm)
- Provides pixel-level detail for measurement
- Allows for free vertical or horizontal movement of ruler on screen
- The ruler will not interfere with other apps running at the same time. instead, “Ruler on Call” allows you to measure objects and help position them in any other apps, especially when they don’t have a built-in mechanism for object alignment or resizing guidance.
- Currently does not support full-screen mode

“Ruler on Call EZ” lets you use a ruler over other app’s screen to help you stay productive. You will definitely love its utility and ease of use.

Need more features? Check out the Full version of Ruler on Call on the Mac App Store today.

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Ratings and Reviews

2.1 out of 5
14 Ratings
14 Ratings
CleeTheDog ,

It measures pixels

I needed a pixel ruler. It measures pixels and works well. You can customize the hotkeys if you don’t like the default Cmd-Option combo. Would be nice if there was an option to display without holding the hotkeys down but I don’t need it much so not a problem. It might be somewhat misleading to state that it measures in different units when this FREE version doesn’t but I guess that is what “Premium” means. I don’t need other units so not worried.

fsfsdfg ,

Very useful for pixel measurement on screen

Great ruler for pixel measurement. But keyboard shortcuts don’t seem to work as expected. I set it to show up with Cmd-Ctrl-Alt, but pressing Cmd-Ctrl shows up already without even pressing the Alt. Please fix the bug. Thank you.


Does not do what it advertises

I wanted to use it to accurately assess the size of small objects listed in mm when I’m shopping - There is no way to easily switch the ruler between units as it indicates above - it opened up in pixels and there it stayed. Pixels are of no use to me. It’s a good thing I have an app zapper - this thing got zapped immediately.


Stony Labs, LLC
6.5 MB
OS X 10.7 or later
Age Rating
Rated 4+


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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