To do Alt + H W S on Mac in Excel, download and install Accelerator Keys, then press Option, followed by H, W, and S.
Command: Shrink to Fit
This is how to do Alt + H W S on Mac in Excel with Accelerator Keys, the native ribbon and alt key shortcut solution for Mac users who get more done with Excel.
Alt + H W S toggles the Shrink to Fit option for selected cells. When enabled, Excel automatically reduces the font size of cell contents so that all text fits within the current column width without wrapping or overflowing. This is useful when you want to keep column widths fixed while ensuring all content remains visible.