About Screen Ruler
A precision on-screen ruler for measuring UI elements, images, and web layouts in pixels, centimeters, and inches. Supports DPI adjustment for physical accuracy on any display.
How to Use
Drag the ruler anywhere on your screen. Resize by dragging the ends. Rotate for diagonal measurements. The ruler stays on top of other windows. Keyboard arrow keys for precise 1-pixel positioning.
Measurement Units
Pixels: Exact pixel measurements for web design and UI development. Centimeters: Physical measurements for print and real-world objects. Inches: Physical measurements for US/imperial systems. The ruler automatically shows measurements in all units simultaneously.
DPI Calibration
For accurate physical measurements (cm/inches), calibrate your screen's DPI. Place a credit card (standard 85.6mm ร 53.98mm) on screen and adjust the DPI slider until the ruler matches. Once calibrated, all physical measurements are accurate.
Use Cases
Web designers: Measure element sizes, margins, padding, and spacing. Graphic designers: Check dimensions of images and layouts. UI/UX designers: Verify design specs against implemented designs. Developers: Debug layout issues and responsive breakpoints. Print designers: Measure physical sizes on screen before printing.