On-Screen Ruler
100% Free UtilityA calibrated on-screen pixel and physical unit ruler with draggable guides for precision alignment.
Processed in browser — zero server uploads
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Active Measurement
250 px
ΔX: 250 px·ΔY: 0 px
Inspector & SettingsStudio Specs
Display PPI:96 PPI
Workflow Guide
How to use On-Screen Ruler in 3 steps
01
Calibrate Physical Screen PPI
Hold a standard credit/debit card up to your display and drag the slider to match its physical width.
02
Measure Points & Distances
Click and drag across the canvas or upload your artwork to measure exact pixel gaps, padding, and physical sizes.
03
Copy Measurements
Readouts update in real time in px, mm, cm, or inches with single-click copy buttons.
Production Questions
Frequently Asked Questions
Web browsers cannot detect the physical pixel density (PPI) of your external monitor or laptop panel. Matching an ISO credit card (85.60mm) establishes your exact screen PPI for true 1:1 physical measurements.
Next in Workflow
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