Metric Scale Ruler

Your browser does not support the canvas element.

PPI : , scale ratio :

Variable Scale Ruler

This is an online scale ruler that could be calibrated to actual size and the scale ratio is variable that could be set by yourself, you can set the scale ratio according to your needs, eg. 1:50, 1:75, 1:100, 1:250, 1:500 ...etc. scale with metric units, centimeters(cm), meters(m) and kilometers(km). In order to let get you the most accurate measurement the length, we strongly recommend that you calibrate the ruler first, set the pixels per inch to your own device. If this ruler is useful to you, maybe your friends need it too, welcome to share it.

How to use this metric scale ruler ?

How to adjusting this scale ruler to actual size

There are some ways to know the pixels per inch(PPI) to your device.
  1. My laptop has a wide screen (13.6"x7.6"), and resolution is 1366x768 pixels, 1366 / 13.6 = 100.44 PPI. Screen resolution of current device is pixels.
  2. Search "display by pixel density" online, check if there has your device's brand and model, i am lucky and found my screen has 100 PPI.
  3. Use standard objects to compare lengths, check your wallet, use any paper money to be our compare object, then search "the width of your paper money" online, when you know the width, you can adjust the ruler's PPI setting by it, you can compare to any standard object, the longer the more accurate.
  4. The most accurate way, after i measure the size of virtual ruler by an actual ruler, i found the markings are not very accurate at 30cm, so i adjust the default pixels per inch(PPI) to 100.7, now i get an online actual size ruler.
  5. Each device has it's own PPI, eg. my laptop is 100.7 PPI, my mobile phones (Sony Xperia C5, OPPO R11 Plus) are both 122.6 PPI, Xiaomi Mi Pad 3 is 163 PPI. sorry, I don't have an iPhone to test for you, too expensive to me 😛

Save the pixels per inch (PPI) according your own device, then you can use this ruler next time.
Pixels per inch : , show ruler adjuster

Dragging ruler adjuster left or right to fit the size of your reference object, remember to save the setting for next time, after save the setting, refresh your brower to check the result. On the most popular browsers you can press the F5 key or click on the refresh button.

Scale Conversion Calculator

If you would like calculate the scale length or real length, we have a scale conversion calculator, it can help you quickly and easily calculate the scale length, welcome to try it.

What do you think about this virtual scale ruler ?


Try the scale ruler on your smartphone

Scan QR Code To Open Browser

Online Virtual Rulers

Share to your good friends

Welcome to share this online scale ruler to your freineds, maybe they will like it.

Length Converters

How to use the scale ruler

A scale ruler a tool for measuring distances and transferring measurements at a fixed ratio of length; eg. architect's scale or engineer's scale.

An Architect's or scale ruler is designed for use in determining the actual dimensions of a distance on a scaled drawing. Most architectural, construction and engineering drawings and blueprints are scaled to allow for large areas, structures or items to conveniently fit on a reasonable size of paper.

Our virtual scale ruler has variable ratio, it could be set the ratio by yourself, eg. 1:10, 1:30, 1:75, 1:200, 1:500 ... The upper half of this scale ruler is the actual length; the lower half is the length calculated by the ratio.

Angle Measurement | Facebook Emoji
Inch to CM | Calculate Cubic Feet
Grams To Ounces | Color Matching
Promotional Products | Corporate Gifts
Custom Wristbands | Custom Lanyards