Sometimes a number with decimal places can appear rounded on your worksheet. This happens when the column isn’t wide enough for the entire number, or when its format is set to show a smaller number of decimal places than your original number contains.
For example, when you enter a number in a cell that’s formatted as General, like all cells on a new worksheet, Excel automatically shows fewer decimal places to make the number fit in the cell. The number in cell A1 below appears rounded, but the entire number is still visible in the formula bar at the top of the worksheet and used in calculations.
To stop rounding the number in the cell, click the Increase Decimal button on the Home tab until you’ve reached the number of decimal places you want to show.
As you increase the number of decimal places, the format changes from General to Number, and the column width adjusts automatically.
Note: If the column width doesn’t adjust and ######## appears in the cell, change the column width by doubleclicking the right border of the column header.
Increase the decimal places for a lot of numbers at once
If you have a lot of numbers that have been rounded, or to prevent numbers from appearing as rounded at all, you can increase the decimal places of a number format and then apply it to the numbers in your worksheet.

On the Home tab, click next to Number.

In the Category list, pick the number format you want to use, making sure it has decimal places, like Number, Currency, Accounting, Percentage, or Scientific.

In the Decimal places box, enter the number of decimal place you want to show.