Long numbers in Excel can be easier to read when you reduce the numbers of digits displayed on the worksheet. The simplest fix in many cases is to change the display format to decrease the number of decimal places. However, if you want to change the actual cell values, or you want to reduce the number of significant digits to the left of the decimal place, use Excel's rounding function instead.
Reduce Decimal Places
Highlight the cells you want to modify.
Select the "Home" tab.
Click the right arrow in the Number section of the ribbon to decrease the decimal places. Keep in mind this changes only what you see on the screen; to change the actual values in the cells for use in computations, use the ROUND function instead.
Select an empty cell in your worksheet.
Enter the ROUND formula using the following format (assuming your number is in cell A1): \=ROUND(A1,x)
Replace "x" with the number of significant digits you want to keep. For example, to round 1.377 to 1.38, replace x with "2". If you want to eliminate significant digits before the decimal place, use a negative number. For example, to round 145,345 to 145,000, replace x with "-3".
Information in this article applies to Excel 2013 and 2010. It may vary slightly or significantly with other versions.