Ruler (inch) online

• Inches ruler
• cm/mm ruler

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JustFreeTools provides you with an easy to use, free printable online ruler that will save you to ever look for a ruler again! For Letter as well as A4 sized paper, inches as well as centimeters.  Due to the easy fold mechanism on the sides, the paper ruler can be used for measuring and drawing as well. 

Some cool facts about rulers you probably didn't know!

The Invention of the First Ruler

In the past, humans have used body parts as ways to measure distances or objects, for example, a hand or foot. The first noted ruler in history, however, dates back to 2650 BC. The first ruler did not look like the ones we have in our stockroom. The first ruler was actually a copper alloy rod; however, there were rulers made of ivory in 1500 BC.

The Metric System

The metric system is the decimal measuring system based on the litre, metre and gram as units of capacity, length and weight/mass. In 1799, the metric system was introduced as the existing system was impractical for trade during the French Revolution. The idea was first proposed in 1670; however, it was only standardised in the 1790s, by the French.

The metric system was then introduced into the UK at the start of 1965.

Different Forms of Rules

The wooden ruler dates back to the 16th Century; however, we now have different forms of rulers. For example, we have metal, wooden, rubber and folding rules to use. The first folding ruler was created in 1851 by Anton Ullrich. The first flexible ruler, however, was invented back in 1902 by Frank Hunt.

Other forms of rulers include a desk ruler, a steel ruler, a carpenter's rule, a seamstress tape and even a tape measure.

Uses of a Ruler

A ruler has had many uses throughout history but has always been a prominent tool in Geometry. Different types of rulers can be used in different industries, for example, in tailoring, software, architecture, design and more. The printing industry and other industries utilise different types of rulers as well. The most notable use of a ruler, however, is in office spaces and schools. A pencil case for school, college or university is not complete without a durable and reliable ruler.

How to Read a Ruler in Inches

If you’re American, inches are the measurement you probably know better than centimeters, which are sometimes included on your standard 12-inch, or 1-foot, ruler.

Right away, you should be able to tell that this ruler uses inches, as it’s divided into 12 equally spaced areas (labeled 1-12), and we know there are 12 inches in a foot (ignore the cm below).

Now, notice the lines between each inch, with some longer and some shorter than others. Each of these tiny lines represents a fraction of an inch. There are five different lengths of lines in total.

Each inch is divided into 16 lines, meaning that the space between each line is 1/16 inch long—this is the smallest length you can measure with a ruler. (Note that some rulers only go down to 1/8 inch lines, whereas others go down to 1/32 inch lines.)

The inch is the biggest unit on a ruler and is represented by the longest line. Each 1-inch line is labeled with a number indicating what inch it is on the ruler (as the image above shows).

The second-biggest unit on a ruler is the 1/2 inch, which is represented by the second-longest line. These typically aren't labeled but might be on some rulers (in which case you'd see numbers such as 1 1/2 in, 2 1/2 in, etc.).

The 1/2-inch line is located midway between every inch on a ruler. The midpoint between 7 and 8 inches, for instance, would be 7 1/2 (or 7.5) inches.

The third-biggest lines on a ruler are the 1/4 inch lines, which appear midway between the 1/2 inch and whole inch lines.

Next is 1/8 inch, which is the second-smallest unit of a ruler. The 1/8 lines are found midway between each 1/4-inch line.

If you counted in 1/8-inch increments, you'd find that the second line after 0 equals 1/8 inch, the fourth line 2/8 (1/4) inch, the sixth line 3/8 inch, the eighth line 4/8 (2/4 or 1/2) inch, the 10th line 5/8 inch, the 12th line 6/8 (3/4) inch, and the 14th line 7/8 inch.