Core Features
Calibratable ruler
Match the scale to a known length and save calibration per device.
CM and inch scales
Switch between centimeters and inches for everyday measurement.
Magnifier assist
Use the magnifier to align edges and marks with more confidence.
Haptic feedback
Feel subtle feedback as you adjust measurement marks.
What can you measure?
Small objects
Match the scale to a known length and save calibration per device.
Stationery
Switch between centimeters and inches for everyday measurement.
Frames
Use the magnifier to align edges and marks with more confidence.
DIY projects
Feel subtle feedback as you adjust measurement marks.
About accuracy
Screen Ruler adapts its scale for known iPhone and iPad device profiles even before calibration. If you notice an offset, calibrate with an object of known length to better match your device.
Frequently asked questions
What is Screen Ruler?
Screen Ruler turns your iPhone or iPad screen into a calibratable digital ruler.
How accurate is it?
Even before calibration, Screen Ruler adapts the scale for known iPhone and iPad device profiles. If you still notice an offset, calibrate with an object of known length to better match your device.
Can I use inches?
Yes. Screen Ruler supports both centimeters and inches.