The internet offers solutions for pretty much anything. For instance, if you don’t have a physical ruler handy, you can try a free virtual one available online. There are websites that offer online virtual rules that can help you to measure objects in cms/mm or inches. Usually, these rulers are calibrated in 3 ways. One is by referring to your monitor pixels per inch (PPI), the other one is by comparing the size of common items and also by referring to your screen size in inches. In this list of online rules, you will find options that work with different calibration methods. The online rulers that we have selected, are organized according to the type of calibration used. Keep in mind that in general, online rulers are less accurate than physical ones. This is particularly true when it comes to online rulers calibrated according to the size of your screen.
Compare to common objects – notes, cards and more
Online Ruler
Online Ruler is a virtual tool where you can measure the size of any object within your computer or mobile screen. In other words, it’s a web-based application that provides a graphical representation of a ruler on your screen. It’s useful when you don’t have a physical ruler handy. It shows the measurements in inches and centimeters. Also, it allows you to calibrate the ruler to ensure accuracy. Moreover, you can change the PPI(Pixels per inch) to adjust the ruler based on your screen size. In addition, there is an option to show the graduation of inches.
Ruler.onl
In Ruler.Onl, you will find an efficient and complete on-screen measuring tool that supports inches and centimeters. The Online Ruler allows you to measure the true size of small items. It works on any internet enabled device, including laptops, tablets and smartphones. This virtual ruler is a handy alternative, if you don’t have a physical ruler. It offers a maximum length of 20 inches/50 cm, when you use a device with a large screen. Keep in mind that before using the ruler, you need to calibrate it. The website offers easy to follow instructions to do so. Furthermore, it provides detailed information that allows you use the ruler correctly and take advantage of its practical functionality.
PiliApp Online Ruler
This convenient ruler created by PiliApp focuses on flexibility. It is possible to move the ruler freely on the screen. You just need to select “drag it”. In addition, if you don’t know what is the size of your screen, you can use the comparing tool that PiliApp offers here: https://www.piliapp.com/actual-size/what-is-my-monitor-size/
The online ruler is convenient and the monitor size tool uses objects that you may have handy and that are relevant to your location.
LifeSizer Online Ruler
This online ruler also works by comparing commonly used objects such as banknotes and cards. The website offers a very simple interface and you can add your own images or click on the image that appears on the website to see the ruler in its actual real life size. The ruler supports both metric (cm and mm) and inches. You can see additional actual size images on the website.
Monitor Pixels Per Inch
Actual Size Ruler
This online ruler stands out thanks to its precision. Using your monitor pixels per inch (PPI), this ruler shows the actual size of the ruler. It is highly accurate and you can adjust the graduation of an inch on the ruler. You can check this PPI calculator to find out the PPI of your monitor: https://www.sven.de/dpi/. The ruler is available in both metric and inches. The interface of the website is simple and the online ruler can be used without hassle.
Screen Size
iRuler.net
Here is another simple online ruler that is calibrated based on the size of the screen. Thanks to its machine learning technology, it can recognize the size of your screen and it shows you a ruler in actual size, but if it doesn’t get it right or you are using a different monitor, you can select the dimension of the monitor. Also, by specifying the right size, you help to make the ruler smarter. In order to ensure that the ruler that appears on the screen is the actual size, you can measure a common object with standard size such as an iPhone or a banknote. You can simply check online what is the measure of the object and then use the ruler to measure the object and see if you get the same results.
Actual Size Online Ruler
Created by Ehi Kioya, this ruler is powered by HTML5 and JavaScript and it works using the canvas element. The ruler is dynamic and it can be adjusted/calibrated by selecting the options available. The website detects the resolution of your screen based on the reading that your operating system does of your monitor size. If the data is wrong, you can manually select the correct display dimensions.
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