You need to track key metrics for performance. Open rate shows how many people read your email. Click-through rate measures the number of clicks on links. Bounce rate tells you how many emails failed delivery. Unsubscribe rate shows how many people left your list. Conversion rate tracks the number of completed actions like purchases. Delivery rate confirms the percentage of emails that reached inboxes. Response rate measures direct replies from recipients. Spam complaint rate indicates how many marked your email as spam. Each metric provides valuable insights. You can adjust your strategy based on these metrics for better results.