Autoreply to Filtered Gmail Messages with Google Scripts

This Google Script, originally published by @rboyd, scans for lengthy emails in your Gmail mailbox (messages that have more than 100 words) and sends an auto-reply requesting the sender to resend the email after editing to less than 100 words. The long email is archived (moved away from the Inbox) after the auto-reply has been sent. You can set it up as a trigger to auto-run every 15 minutes.

Also see: Email Auto-responder for Gmail

// Credit: https://gist.github.com/rboyd/5027691

function deleteLongEmails() {
  var WORDLIMIT = 100;

  // Process only new emails in inbox that have not been read and receive in the last day
  var threads = GmailApp.search('to:me is:unread in:inbox newer_than:1d');

  for (var i = 0; i < threads.length; i++) {
    // Ignore email conversations
    if (threads[i].getMessageCount() == 1) {
      var msg = threads[i].getMessages()[0];
      var word_count = msg.getPlainBody().split(' ').length;

      if (word_count > WORDLIMIT) {
        msg.reply('Your email is too long. Please resend after editing it to less than 100 words.');
        GmailApp.moveThreadToArchive(threads[i]);
      }
    }
  }
}

Amit Agarwal is a web geek, solo entrepreneur and loves making things on the Internet. Google recently awarded him the Google Developer Expert and Google Cloud Champion title for his work on Google Workspace and Google Apps Script.

Awards & Recognition

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