Rounding decimals is a simple way to estimate values without having to write countless numbers to the right of the decimal point. You can round decimals to the nearest whole number or the nearest tenth, nearest hundredth, or nearest thousandths decimal. We’ll show you how.
Rounding Decimals: How It Works
Let's explain how rounding numbers with decimals works using the following value:
This decimal has a ten-thousand place value, meaning that there are four numbers to the right of the decimal point. We want to round this to the thousandths place.
When you round decimal numbers, you must decide whether to round up or down by looking at the last last digit of the decimal number. If the digit is a value of 5 or above, you will round up. Since the last digit in this example is 9, we will round the place to its left, the thousandths place, up to 1:
If the last digit in the decimal number is 4 or lower, we will "round down" by keeping the next left digit the same. Let's use the below example to round from the hundredths place (two decimal places) to the tenths place (one decimal place to the left):
Since the value of 3 is lower than 5, we will round down to the tenths digit of 2:
Here are some other examples of rounding down to the nearest whole number or decimal place value:
You Need to Know How Rounding Decimals Works
When rounding decimals, all you have to do is determine whether the last digit of the decimal means the number to its left should be rounded up or down. This depends on whether its value is 5 or higher.