Free Online Ruler — cm and Inches, Actual Size
Hold an object to the screen and measure. Calibrate once for accuracy.
…
How to do it
- 1Choose your settings
Fill in the details or pick the options you need.
- 2See the result
The preview updates right away as you change things.
- 3Download or save it
Save the result to your device. Nothing is sent to or stored on a server.
About this tool
Measure small objects with your screen. The ruler shows centimetres or inches in the browser. Because every screen is different, you can calibrate it once with a bank card (85.6 mm wide) and the setting is remembered on your device. It is a handy guide, not a precision instrument.
Frequently asked questions
How accurate is it?
After calibration it is usually within a millimetre or two. Browser zoom changes the size, so keep zoom at 100 percent.
How do I calibrate it?
Press Calibrate, hold a bank card to the screen and drag the slider until the blue box is the same size, then save.