Open rate measures how often emails are opened, but privacy features can make it unreliable. Learn what open rate means and which metrics to prioritize.
Email open rate is the percentage of delivered emails that register as opened. Traditionally, opens are tracked using a tiny image pixel that loads when the message is viewed, which triggers an “open” event.
Open rate is useful for comparing subject lines and list segments, but it has limitations. Image blocking and privacy protections like Apple Mail Privacy Protection can inflate or distort opens, making them less reliable as a measure of true attention.
Because of these changes, clicks, replies, and conversions are often more meaningful. Use open rate as a directional signal, but base key decisions on engagement metrics that are harder to spoof or auto-trigger.