There are several methods to change capital letters to small letters (lowercase) in Excel. The most common and straightforward way is to use the LOWER function. Here's a simple step-by-step guide:

1. Select an empty cell where you want the lowercase version to appear.
2. Enter the formula: =LOWER(A1) (replace A1 with the cell containing the capital letters).
3. Press Enter, and the text will appear in lowercase.
4. To apply this to multiple cells, drag the fill handle from the corner of the cell with the formula down to other cells.

Additionally, after converting text with the LOWER function, you can copy the results and use Paste Special > Values to replace the original text with the lowercase text only, removing the formula. As a shortcut, Excel does not have a direct key to toggle case, but using formulas like LOWER is effective. Alternatively, the keyboard shortcut Shift + F3 cycles through uppercase, lowercase, and proper case when editing text in a cell. These methods provide quick and easy ways to transform capital letters into lowercase in Excel.