To do Alt + M J on Mac in Excel, download and install Accelerator Keys, then press Option, followed by M, J.
Command: Calculate Sheet
This is how to do Alt + M J 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 + M J calculate Sheet recalculates only the formulas in the active worksheet. This is faster than Calculate Now when you only need to update one sheet.