Measure the length and distance of objects on your screen online. Supports multiple units including pixels, millimeters, centimeters, and inches.
When you need to accurately measure the dimensions of web elements or design drafts, a physical ruler cannot meet your screen measurement needs. An online screen ruler draws an adjustable scale on your screen to calculate and display the length of target objects in real time. One pixel (px) is the smallest display unit on a screen. Through DPI conversion, pixel length can be converted into physical dimensions such as millimeters (mm), centimeters (cm), or inches (in).
How do I calibrate the ruler for accurate results?
Use a standard-sized credit card (85.6 × 54 mm) as a reference. Adjust the tool's DPI settings to match your screen's actual resolution.
Does browser zoom affect measurement results? Yes. To ensure accuracy, please keep your browser zoom level at 100%. Non-standard zoom levels will cause measurement deviations.
Different monitors have different DPI parameters, so calibration is recommended before first use. Avoid using the tool in a browser with a zoom level other than 100%. This tool is designed exclusively for on-screen measurements and is not suitable for measuring physical objects.
For web designers, it is recommended to measure interface elements in pixels. Typical measurement examples: a standard button width is usually between 120-160px, and a navigation bar height is about 50-80px. When measuring, you can adjust the ruler's color to contrast sharply with the background to improve visibility.
