Just what is a good open rate average, and is there an open rate formula? In our world we talk a lot about open rates, and why it's so important to track them (you can read more about the importance of tracking open rates here). While open rate averages vary widely across industries, senders, ESPs, and ISPs, and there is no real open rate formula, a very general rule of thumb is that inbox providers and ISPs like to see a consistent 20% or better open rate in order to keep putting the email that you send flowing into the inbox, and help to avoid your landing in the spam folder. But what is less talked about is what causes failure to opens (FTOs) and how to prevent them.
