Screen Ruler
On-screen measurement tool with rulers in centimeters, millimeters, inches, and feet. Calibrate to your display.
Created by samyakrajbayar
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How to Use
• Find an object with known dimensions (credit card is 85.6mm wide, recommended) • Hold the object against the colored calibration bar on your screen • Enter the exact size of your reference object in the input field • Select the correct unit (millimeters, centimeters, or inches) • Click "Calibrate" button to set up your screen's measurement ratio Once calibrated: • Click unit tabs (Centimeters, Millimeters, Inches, Meters, Feet) to switch between different rulers • Use the displayed ruler to measure anything on your screen accurately • Check screen information section for your display's resolution and DPI Important notes: • Keep your browser zoom at 100% for accurate measurements • Use a flat, rigid object for calibration reference • The tool calculates your screen's pixel density to provide precise measurements • Longer reference objects provide better accuracy This tool helps designers, developers, and anyone measure on-screen elements without a physical ruler.