The Lesson
Engineering notation is a way of writing a number. It is written as a number between 1 and 1,000 multiplied by a power of 10 that has an exponent that is a multiple of 3. The number below is written in engineering notation. It is said as "123.4 times 10 to the 3".
- 123.4 is between 1 and 1,000.
- 103 is a power of 10. The exponent is 3, which is a multiple of 3. 106, 109 and 1012 also have exponents that are multiples of 3.
Understanding Engineering Notation
A number represented in engineering notation is written as a number between 1 and 1,000 multiplied by a power of 10 that is a multiple of 3. The power of 10 is written as a 10 with a raised number by its side. The raised number is called an exponent.
123.4 × 103 = 123.4 × 10 × 10 × 10 = 123.4 × 1,000
So 123.4 × 103 represents the number given by 123.4 × 1000, which is 123,400.
123.4 × 103 = 123,400
Why Is Engineering Notation Useful?
Engineering notation is useful because it allows us to write very large or very small numbers in a shorter, standard way. Some examples of numbers written in engineering notation are shown below, along with the numbers written in full. Notice that it can save you writing lots of 0s.

Converting a Number into Engineering Notation
Engineering notation is a useful way to write long numbers.

Read more about converting numbers to engineering notation
Converting Engineering Notation to a Number
When you see a number written in engineering notation, you must know what number it represents.

Read more about converting engineering notation to numbers
Note
Number Between 1 and 1,000
The number in engineering notation (that multiplies the power of 10) is between 1 and 1,000. It can include 1, but not 1,000.Powers of 10
A power of 10 is 10 raised to a exponent. For example, 103 is a power of 10. The small 3 written beside the 10 means it is raised to an exponent of 3. This means 10 is multiplied by itself 3 times.
103 = 10 × 10 × 10
The answer will have 3 0s after the 1:
103 = 1,000
What Is a Multiple of 3?
The exponent of the power of 10 in engineering notation must be a multiple of 3. A multiple of 3 is a number that results from multiplying 3 by a whole number. Multiples of 3 are:
3, 6, 9, 12, 15, 18, 21...
Multiples of 3 can be negative as well:
−3, −6, −9, −12, −15, −18, −21...
Other Ways of Writing Engineering Notation
To write engineering notation on a keyboard, the ^ symbol is used for the exponent of 10 (103 = 10^3):
5.2 × 103 = 5.2 × 10^3
On a calculator, the E symbol is used to represent a power of 10 (×102 = E2):
5.2 × 103 = 5.2E3