Press the vertical ellipse button (three dots) and choose “Exit.”

Users also can click Alt-F and X on their keyboard. On a Mac, users can close all of your Chrome windows at once by tapping on the “Chrome” menu in the menu bar at the top of the screen, and then selecting “Delete Google Chrome.” You could also click the Command+Q button on your keyboard. If you turn “Warn Before Quitting” on, you will see a notice saying “Hold Command+Q to Quit” so if you press Command+Q.  you’re going to have to hold Command+Q down for a minute for the quitting process to take place.

Thereafter, every one of your Chrome browser windows will be shut down quickly.

Ways to close all google chrome windows at once - 15Ways to close all google chrome windows at once - 68