Calibrated Online Ruler
Measure the calibration bar with a real ruler. Enter its measured length in cm, then calculate the scale.
Test area
Results
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How to use this tool
Measure the calibration bar with a real ruler. Enter its measured length in cm, then calculate the scale.
Method and units
CSS px/cm = calibration width(px) / measured length(cm)
What this test can and cannot tell you
Inputs determine the calculation. Calibrate the ruler on this screen and again after zoom or screen changes.
Results reflect events and signals available to your browser. Settings, permissions and device support can affect them; they do not certify that hardware is healthy or faulty.
Input tests run in your browser. Camera and microphone access starts only after you request it.
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