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Ever needed to measure something but found yourself without a ruler? Our online ruler is here to help you solve this problem! It's a virtual ruler that lets you measure small objects in inches or centimeters right on your screen. Whether you're using a computer, tablet, phone, or even a smart TV, you can make accurate measurements.
Yes, our online ruler made to be as accurate as possible. However, the accuracy can depend on your device screen size, its pixel density (PPI), and your privacy settings. That's why we have included a way for you to calibrate the ruler to match your specific screen.
We made our ruler as simple as possible right out of the box.
We try to detect your screen size and calculate the screen PPI automatically, but sometimes, for various reasons, it doesn't detect it correctly. You can adjust this setting in the settings button by just entering your screen size or PPI manually. We also made a PPI Calculator if you feel it's better, you can use it.
To use your phone as a ruler:
This web app turns your phone into a handy, portable ruler that you can use anytime, anywhere.
Works on any modern browser — Chrome, Safari, Firefox, Edge, Opera — across desktop and mobile. Auto-detection covers: