Measurement of Length
Measuring length means measurement of the length of any object with the help of measuring tools like a ruler, measuring tape, etc. For example, the length of a pencil can be measured in inches using a ruler. The height of students in a class can be measured using a feet scale. There are units of length like inches, centimeters, meters, feet, etc. Let us learn about the measurement of length in detail in this article.
1.  What is Measurement of Length? 
2.  How to Measure Length? 
3.  Units of Length Measurement 
4.  Tools to Measure Length 
5.  Measurement of Length Chart 
6.  FAQs on Measuring Length 
What is Measurement of Length?
Measurement of length is defined as the act of measuring the length of objects in some specified units which can be standard or nonstandard. The skill of measuring the lengths of objects and understanding the units of length is very crucial as it helps us to interact with our environment in a more organized manner. Imagine going to a store with your friend and observing a beautiful vase to place in your drawing room. But if you want to tell the length of that vase to somebody who is not there, how will you do it? We can do that if we know its value in a certain unit, say 4 feet. Thus, measuring length is an important skill to be used in our everyday life. Many times, we do not use a particular scale or tool to measure length but only guess it based on our understanding of units of length and observation. Look at the image given below showing the act of measurement of the length of a pencil using a ruler. Here, the length of the pencil is 8 centimeters which is one of the units of measuring length.
How to Measure Length?
There are two sides of a ruler, centimeter/millimeter and inches. The steps to measure length using a ruler are given below:
 Step 1: Choose the unit in which you want to measure length. If you want a value in centimeters, then take the centimeters side of the ruler. If in inches, then take the inches side of the ruler.
 Step 2: Place the object beside the ruler starting from point 0 on it.
 Step 3: Look at the endpoint and mark the value. For example, in the above figure, the length of the pencil is from 0 to 8 cm.
Units of Length Measurement
Length can be measured in different units like centimeters, inches, meters, or by using a handspan, foot span, etc. The units of measuring length can be classified into two types: Standard units of measuring length and nonstandard units of measuring length. Look at the chart below showing units of length.
Standard Units of Measuring Length: Such units are predefined and do not change person to person or object to object. If two or more people will measure the length of the same object using any standard unit, say inches, they will get the same result. Some examples of standard units of length are meters, centimeters, inches, feet, yards, etc. Standard units can again be divided into two types: Imperial units and metric system units.
The imperial system of units is the system of units first defined by the British, to measure different quantities. The Weights and Measures Act of 1824 and the Act of 1878 established the British Imperial System on the basis of precise definitions of selected existing units. Some commonly used units in the imperial measurement systems are.
Let us see the unit conversion table for the imperial measurement system of length.
1 nautical mile  1.151 miles  1852 meters 
1 mile  1760 yards  1609 meters 
1 furlong  220 yards  201 meters 
1 rod  5.50 yards  5.029 meters 
1 fathom  6 feets  1.829 meters 
1 yard  3 feets  0.9144 meters 
1 foot  12 inches  0.3048 meters 
1 inch  0.083 foot  0.0254 meters 
We also have metric units to measure length. These units include kilometer, hectometer, decameter, meter, decimeter, centimeter, and millimeter. There is a special relationship shared by these units. Among these units, meters is the base unit. The relationship of every other unit with the base unit (meters) is given below:
 1 kilometer (km) = 1000 meters (m)
 1 hectometer (hm) = 100 m
 1 decameter (dam) = 10 m
 1 decimeter (dm) = 1/10 m = 0.1 m
 1 centimeter (cm) = 1/100 m = 0.01 m
 1 millimeter (mm) = 1/1000 m = 0.001 m
Look at the chart of units of measuring length under the metric system given below.
Nonstandard Units of Measuring Length: Such units do not have a fixed measurement in numbers. They vary from person to person and from object to object. For example, if a child and his father measure the length of a rectangular wall using their handspan, it is most likely that they will get different values. This is because the handspan of a child is usually smaller than an adult. Some of the nonstandard units of length are handspan, foot span, finger width, pace, cubit, a thread or a rope, etc.
SI Unit of Length
The SI unit of measurement of length is meter (m). As shown in the above chart, the meter is the base unit of length. Its value in some other units are given below:
 1 m = 100 cm
 1 m = 1000 mm
 1 m = 0.001 km
 1 m = 39.37 inches
 1 m = 1.09361 yards
 1 m = 3.28 feet
Tools to Measure Length
There are different tools for the measurement of the length of different items. The list of the most commonly used tools for measuring length is given below:
 Ruler
 Tapes
 Yardsticks
 Meter sticks
 Feet/foot scale
Measurement of Length Chart
The measurement of length chart helps us to convert a unit to another unit easily. For example, if we know that 1 yard = 36 inches, we can easily convert 3 yards to inches by multiplying 3 by 36. The measurement of length chart is given below showing the conversion of metric units, imperial units, metric to imperial units, and imperial to metric system units of length.
Metric System 
1 cm = 10 mm 1 m = 100 cm 1 m = 1000 mm 1 km = 1000 m 

Imperial System 
1 feet = 12 inches 1 yard = 3 feet 1 yard = 36 inches 1 mile = 1760 yards 1 mile = 5280 feet 
Metric to Imperial System 
1 cm = 0.3937 inches 1 m = 39.37 inches 1 m = 3.28 feet 1 km = 3280.84 feet 1 km = 0.62 miles 1 km = 1093.61 yards 
Imperial to Metric System 
1 inch = 2.54 cm 1 foot = 30.48 cm 1 yard = 91.44 cm 1 foot = 0.3048 m 1 mile = 1.6 km 1 mile = 1609.34 m 1 yard = 0.9144 m 
Tips and Tricks on Measuring Length:
 It is important to convert different units of length into one before solving the questions.
 Meter is also called the SI unit of length or base unit of length.
 The USA follows both metric as well as the imperial system of measurement.
► Related Topics
Check these topics related to the measurement of length in math.
Measurement of Length Examples

Example 1: A swing has to be built using a rope of length 7200 inches. If only 420 feet of rope is available, find the length of rope still needed (in feet) to build the swing.
Solution: Given, the total length of rope needed = 7200 inches and the length of rope available = 420 feet. To find the length of the rope still needed to build the swing, we need to first convert 7200 inches to feet.
⇒ 1 inch = 1/12 feet
⇒ 7200 inches = 7200/12 feet = 600 feet.
So, the total length of rope needed in feet is 600 feet. Out of this, 420 feet is available. Thus, the measurement of the length of rope needed = (600  420) feet = 180 feet.
Therefore, the length of rope still needed to build the swing is 180 feet.

Example 2: Can a pencil of length 350 mm fit inside a pencil box of length 45 cm?
Solution: Given, measurement of length of pencil = 350 mm and length of pencil box = 45 cm. Both units are different, so let us convert 45 cm to mm.
⇒ 1 cm = 10 mm
⇒ 45 cm = 45 × 10 mm
= 450 mm
Since 350 mm < 450 mm, the pencil can fit inside the box.

Example 3: How to convert 12 yards to feet?
Solution: Yards and feet are units of measuring length in the imperial system of measurement. There are 3 feet in 1 yard.
⇒ 1 yard = 3 feet
⇒ 12 yards = 12 × 3 feet = 36 feet
Therefore, there are 36 feet in 12 yards.
FAQs on Measurement of Length
What is Measuring Length?
Measuring length is defined as identifying how long is the given object. Length is a quantifiable attribute given to objects in order to identify them and work with them easily.
What is the Smallest Measurement of Length?
The millimeter is the smallest measurement of length. If an object is very small, say the length of the pencil tip, length of our nails, etc, we can measure them in millimeters. On a centimeter ruler, there are 10 small divisions made between 1 centimeter. Each of those divisions is equal to a millimeter.
What is the SI Unit of Measurement of Length?
The SI unit of the measurement of length is a meter which is abbreviated as m. Meter is considered as the base unit. There are units that are greater than a meter (like decameter, hectometer, kilometer) and less than a meter (like decimeter, centimeter, and millimeter). 1 meter is equal to 100 centimeters or 0.001 of a kilometer.
What is the Unit of Measurement of Length Mass and Volume?
Length, mass, and volume can be measured using different units. Some of the commonly used units for measuring length are centimeters, millimeters, meters, inches, feet, yards, feet, etc. Some of the units to measure mass are pounds, ounces, kilograms, grams, centigrams, milligrams, etc. And some of the commonly used units to measure volume are liter, cubic meters, cubic centimeters, etc.
What is the Biggest Measurement of Length?
The biggest unit to measure length is Parsec. It is used to measure space distances. There are approximately 3.26 lightyears in 1 Parsec.
What is the Unit of Measurement of Length?
There are various units to measure length. Units of length can be categorized as standard units and nonstandard units. Standard units are those that have a defined value that is fixed and can be converted to other units. Some examples of standard units are centimeters, inches, meters, yards, etc. Nonstandard units are those that vary from person to person. Nonstandard units include measurement using handspan, foot span, cubit, etc.
How to Teach Measurement of Length?
Teaching measurement of length begins right from grade 1 to further grades. It should start with letting learners know "what do we measure?". This can be facilitated using nonstandard units to measure some reallife objects like the length of a table, blackboard, pencil box, notebook, etc. Then, units of length should be introduced to match the values of lengths found by different people. Following worksheets can be used to teach measurement of length to learners.
What are the Instruments for Measuring Length?
There are various instruments or tools for measuring length such as a ruler, yardstick, meter stick, feet scale, measuring tape, etc.
What are the NonStandard Units of Measuring Length?
Nonstandard units of length include measurement using handspan, foot span, cubit, pace, finger width, thread or rope, etc. Any smaller object used to measure the longer length, say an eraser used to measure the length of a notebook, is an example of a nonstandard unit.
What are the Two Methods of Measuring Length?
The two methods of measuring lengths are the direct and the indirect method. In the direct method, standard units are used, while in the indirect method, nonstandard units are used.
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