Excel Shortcut Keys: Using Ctrl + W (Closes the selected workbook window)

Excel Shortcut Keys

Ctrl + W
Closes the selected workbook window.

Close All file on a single click in Excel 2013 and 2016

Excel Tutorial

Close All file on a single click in Excel 2016

In Excel 2013 & 2016 All the excel files open in separate window so it's not possible to close all the opened file at once. This is by default, there is no option to close all excel workbook/files at once in version 2013 & 2016.
Previous version of Excel workbook/file opened in one window and we can easily have closed all the files just using the Alt+F4. Excel 2013 each excel file open on separate window and continue in 2016 version.
For example, if we have 10 files open we must close all the files separately or hit the Alt+F4 command 10 times.