To ensure the quality of your email list, track the following metrics:
1. Open Rate: The percentage of subscribers who open your emails. 2. Click-Through Rate (CTR): The percentage of subscribers who click on links within your emails. 3. Conversion Rate: The percentage of subscribers who take the desired action after clicking through your email. 4. Bounce Rate: The percentage of emails that could not be delivered to the recipient's inbox. 5. Unsubscribe Rate: The percentage of subscribers who opt-out of your email list.