There are a few indicators that can help you identify if your list is outdated:
High Bounce Rates: If you notice a sudden increase in bounce rates, it’s a sign that your list may contain a lot of invalid addresses. Low Open Rates: A consistent decline in open rates can indicate that your list is not engaging. Inactive Subscribers: If a large portion of your list has not engaged with your emails in the past six months or more, it’s time for a cleanup.