Trash & delete old promotions from Gmail inbox

code.gs

// Go to https://script.google.com/home
// Create a new script, pase all of this, and click run
// The first run will ask you for permissions, and it may time-out before trashing all the emails, so run it again as necessary
// Optionally, create a time based trigger to run the script periodically (when first clearing my email I had it run every ~15 mins, but now once a day)

function purgeGmail() {
  // Paste this query in your gmail search bar BEFORE running the script, and make sure nothing you need is matched
  const search = "category:promotions older_than:1y -is:important -is:starred -has:attachment";
  Logger.log("Removing messages matching: " + search);
  
  
  length = 1;
  
  while(length > 0) { 
    const threads = GmailApp.search(search, 0, 500);
    
    var c = 0;
    for (var i=0; i<threads.length; i++) {
      const thread = threads[i];
      Logger.log("Moving to trash: " + thread.getFirstMessageSubject());
      thread.moveToTrash();
      c++;
    }
    
    Logger.log("Deleted a batch of " + c + " messages.");
    length = threads.length;
  }
}