Gmail mail merge allows you to batch send personalized emails to recipients by dynamically updating four merge tag fields: @first name, @last name, @full name, and @email. To do a mail merge in Gmail using Google Contacts, click Compose, select the Use mail merge icon, and draft your templated message with merge tags. Preview your email to ensure accuracy and set default values if needed. After clicking Continue, you'll receive individual copies of your templated email. Alternatively, you can use contacts stored in Google Sheets by adding column headers, selecting the relevant columns for each merge tag, and linking the spreadsheet to Gmail. This method offers more flexibility but requires some spreadsheet organization. When using mail merge, be mindful of storage limits, avoid CC or BCCing recipients, and consider its limitations compared to email marketing platforms.