Choose Gmail’s Delete All Messages option. To get started, log in to your Gmail account as you normally would. Select all of the messages. Next, under the search bar, check a little box to select all displayed emails. nSelect all Conversations?
Before: After: Use the advanced search operators before and after to narrow down your date range. Click the “select all” checkbox. Click the link for “Select all conversations that match this search. All talks are now selected. Delete must be clicked.
You may search for emails that are no more than a year old. If you put older than 1 year, you’ll get emails that are over a year old. You may also use m or d to separate the years and days. To remove them all, check the Check all box, then choose “Select all conversations that match this search,” followed.
Delete All Your Gmail Emails Inbox. Go to your Gmail account and select the blank square in the example below.
Select More from the left side of the Gmail page. After that, select All Mail from the list. On the left side of the Gmail page, checkmark the checkbox next to Compose.