How to measure pixels on your screen with Screen Ruler

Next, scroll down to the section for Behavior. The first setting here for Capture screen continuously during measuring determines whether the tool continuously measures the screen or takes a single snapshot. For most results, you'll want to keep this switch turned on. However, if you're trying to measure a moving object, such as an animated GIF, or you need to take a screenshot of the measurement, then turn off this switch.

The setting for Per color channel edge detection checks if all the color channels are within a tolerance distance from each other. You can typically leave this turned off. The setting for Pixel tolerance for edge detection can help you more accurately measure certain elements on the screen. For example, Microsoft recommends increasing this value if you need to measure gradients or shadows.

The setting for Draw feet on cross adds “feet” to the cross lines, so you can better see them. And the final setting for Line color determines the color of the measurement lines. Red is the default, but you can easily change this if that color conflicts with the color of the screen.

Also: The best desktops for graphic design