Google Sheets Merge all keyboard shortcut
Mac
Ctrl+Opt+O → M → A
Windows
Alt+O → M → A
The keyboard shortcut for Merge all in Google Sheets is Ctrl+Opt+O → M → A on Mac and Alt+O → M → A on Windows. It replaces the menu path Format › Merge cells › Merge all.
Learn this shortcut without trying
MasterKey is a free Chrome extension. It counts what you keep doing with the mouse in Google Sheets and sticks the top six to the corner of your sheet — each one peels off once you've used it enough. Nothing pops up while you work.
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