Best Tool for Accurate On-Screen Measurements in Centimeters?

[roxoy]

Hey everyone,

I’m currently working on a design project that requires precise measurements directly on my screen. I’m trying to find a reliable screen ruler in cm to help me accurately size elements without constantly switching to physical rulers or resizing windows.

I’ve seen a few browser extensions and downloadable tools, but I’m not sure which ones are accurate or safe to use. Does anyone have recommendations for a trustworthy digital ruler that measures in centimeters and works well on both Windows and macOS?

Bonus points if it’s free or open source.

Thanks in advance!

[dodef]

You can try PixelRuler or ScreenRuler as both support measurements in centimeters and are quite accurate once calibrated. If you're specifically looking for a screen ruler in cm, these tools are among the best for on-screen precision. PixelRuler works on both Windows and macOS, while ScreenRuler is browser-based and doesn't require installation. For open source options, check out KRuler, which is mainly for Linux but adaptable. All are safe, lightweight, and excellent for design tasks.