A quick way to have a number appear as rounded is to change its number of decimal places. Just select the number you want to round and click Home > Decrease Decimal .
The number will look rounded in the cell but the actual value doesn’t change—the full value is used whenever the cell is referenced.
Use functions to round numbers
To round the actual value in cells, you can use the ROUND, ROUNDUP, ROUNDDOWN, or MROUND functions as shown in the following example worksheets.
Round to the nearest number
This worksheet shows you how use the ROUND function to round to the nearest number.
When you round a number, the format of the cell might override what you expect to be shown. For example, if you specify 4 decimal places as the second argument but the cell is formatted to display 2 numbers after the decimal point, the formatting of the cell takes precedence.
Round to the nearest fraction
This worksheet shows you how to round a number to the nearest fraction by using the ROUND function.
Round a number up
This worksheet shows you how to use the ROUNDUP function.
You can also use the EVEN and ODD functions to round up a number to the nearest even or odd whole number. These functions have limited uses, and it's important to remember that they always round up and only to a whole number.
Round a number down
This worksheet shows you how to use the ROUNDDOWN function.
Round a number to a significant digit
This worksheet shows you how to round a number to a significant digit. Significant digits contribute to the accuracy of a number.
The following list provides some general rules to keep in mind when you round numbers to significant digits. Experiment with the rounding functions and substitute your own numbers and parameters to return the number of significant digits that you want.

If a fractional part is 0.5 or greater, the number is rounded up when you use ROUND. If it’s less than 0.5, the number is rounded down. Whole numbers are also rounded up or down following a similar rule that substitutes multiples of 5 for 0.5.

As a general rule, when you round a whole number, subtract the length from the number of significant digits to which you want to round. For example, to round 2345678 down to 3 significant digits, you use ROUNDDOWN with the parameter 4. For example, = ROUNDDOWN(2345678,4) rounds the number down to 2340000, with the "234" portion as the significant digits.

To round a negative number, that number is first converted to its absolute value—the value without the negative sign. When rounding is complete, the negative sign is reapplied. For example, when you use ROUNDDOWN to round 889 to two significant digits results in 880, 889 is converted to 889 and rounded down to 880. The negative sign is then reapplied for a final result of 880.
Round a number to a specified multiple
There may be times you’ll want to do this. For example, when your company ships a product in crates of 18 items, and you want to find out how many crates you’ll need to ship 204 items. MROUND divides the number you want to round by the multiple, and then rounds it up. In this case, the answer is 12, because 204 divided by 18 is 11.333, and will be rounded up to 12 to fit the remaining items. The 12th crate will contain only 6 items.
This worksheet shows you how to use the MROUND function to round a number to a specified multiple.