How to Measure With a Screen Ruler

A screen ruler is useful when you need a quick measurement and do not have a physical ruler nearby. The key is calibration: once the screen ruler knows your display density, it can draw real-world units at the right size.

Steps

• Open Real Screen Ruler.
• Calibrate your screen with auto-detect, screen diagonal, or credit card calibration.
• Place the object against the ruler edge.
• Read the measurement from the nearest tick mark.

Accuracy tip

For the best result, use credit card calibration and compare the on-screen card with a real card.