3 5 On A Ruler

⬇ Specify your screen size for calibration

inch cm

If you want to measure the bodily size of a small object in inches or centimeters and you don't accept a real ruler at hand, this virtual on-screen online ruler will assistance you. You can make the necessary measurements on whatever device that allows y'all to browse the web. This online app works on both computers with a large screen (laptops, PCs, monoblocks or smart TVs) and mobile gadgets (phones, phablets, tablets, due east-ink readers). The maximum length of the ruler (fully visible when displayed on a sufficient screen) is 20 inches, or 50 centimeters (500 millimeters) for the metric scale choice.

💁 How to employ this online ruler

For the ruler to display correctly (i.east., in proportion to the actual physical size), information technology must be calibrated. You can calibrate it in one of the post-obit 2 ways:

📱 💻 📺 Set screen diagonal

This is the most reliable and like shooting fish in a barrel way. Specify the size of the diagonal of your screen in inches ("). Enter this value in the input field located in the lower left corner of the ruler image. So click the or press the button on the keyboard. You can also select the size from the drop-down listing (which opens when you click the button , which is next to the numeric input field). This presents many of the most common options among users.

The diagonal of the current device's display, automatically detected past the browser, is . In well-nigh practical cases, this calculated value does not correspond to the real extent and is instead proposed for consideration as an approximate one for consideration purposes. This circumstance is caused by the existing constraint imposed by the specifics of the interaction of modern web browsers (none of which has the functionality of providing web applications with access to information about the display's physical parameters) with operating systems. Depending on the type and course of device, the likely error varies in a range of up to several centimeters, or 1 inch. Accordingly, to the best possible, the reliability of the indications of the uncalibrated online ruler volition differ from the standard. Nonetheless, the difference may be minimal. In this case, the initially visualized ruler will be suitable for measurements that practice not require high accuracy (especially when measuring small objects).

If you lot practice not know the exact value of your screen'southward diagonal, y'all tin can observe it in the technical documentation fastened to the device, or only search the Net for the model name.
If for some reason this information is difficult to obtain and you have a standard plastic card with y'all, you lot can utilise the second method. ↓
💳 Fit to the width of a plastic card

You tin can also calibrate the on-screen ruler using a bank payment card. Its standard width is 3.37 inches (3 3⁄8 inches), or 85.6 mm (8 centimeters, 56 millimeters) for the metric measurement. For your convenience, the respective sign is plotted under the scale of the ruler. Modify the diagonal value in the input field until the edge of the plastic card attached (oriented horizontally) to the screen coincides with the black stroke to the left of the icon.

Using this method in addition to the kickoff method will allow yous to determine the size of the brandish diagonal. To avert the known inconvenience associated with selecting a number by successive transmission input, bring it to the desired value using the vertical scroll arrows that appear on the right side of the input field when you hover the cursor over it (when using the virtual ruler on a PC).

📏🔧 How the ruler's actual size is achieved

Based on the browser-defined screen height and width, the script:

calculates the diagonal in pixels (it does not matter if the number of virtual pixels on which the browser operates is the actual physical resolution of the display);
calculates the PPI (pixels per inch) of the screen: the resulting diagonally expressed diagonal is divided by the user's diagonal value in inches;
determines the length of the ruler in pixels, the corresponding real 50 centimeters: the PPI value is multiplied past expressed in inches fifty centimeters. For inch scale, it is simply multiplied past twenty.

⚠️ ️Note

Go along in mind that the above instructions for setting upward the ruler are valid merely when the post-obit weather apply:

Standard page calibration aligning in your browser (this is true for desktop browsers). When the scale is zoomed in/out, the ruler calibration will shrink/stretch (forth with other elements on the folio that are bailiwick to transformation during scaling). This volition lead to a significant distortion of the online ruler readings. If you frequently, for example, change the font sizes on sites, exist sure to set up the scale to 100%;
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