Email, Messaging, & Video Calls Email How to Write Gmail Messages in a Bigger Window Use full-screen mode to get more space to compose by Heinz Tschabitscher Writer A former freelance contributor who has reviewed hundreds of email programs and services since 1997. our editorial process Heinz Tschabitscher Updated on May 20, 2020 Email Gmail Yahoo! Mail Tweet Share Email Gmail's default message composition box only takes up about a third of your computer screen. The small size can make writing difficult, especially if your message is lengthy. Fortunately, you can expand the box to take up much more screen real estate. Doing so makes it a lot easier to write long emails without having to scroll through the small box. Write a New Gmail Message in Full-Screen Mode Follow these steps to expand Gmail's message window to full-screen mode: In the upper-left corner of Gmail, select Compose to start a new message. In the upper-right corner of the New Message window, select the Full-screen (diagonal, double-sided arrow) icon. The window opens in full-screen mode for more space to write. To always have the New Message screen open in full-screen mode, at the bottom-right of the New Message window, select the Menu (three stacked dots) icon. Choose Default to full screen. The next time you open a Compose window, it appears in full-screen mode. Reply to a Gmail Message in Full-Screen Mode Follow these steps to open your message in full-screen mode when composing replies or forwards: Open the message you want to forward or reply to. Scroll to the bottom of the message. Select Reply or Forward. Next to the email address of the recipient, select the small arrow. Choose Pop out reply to open the message in a new pop-up window. When the pop-out window opens, follow the steps in the Write a New Gmail Message in Full-Screen Mode section, above.