Engagement rate in Google Analytics 4 is the percentage of sessions that were "engaged" — meaning the visitor stayed for at least 10 seconds, triggered a conversion event, or viewed at least 2 pages. It's essentially the inverse of bounce rate but more nuanced. A 65% engagement rate means 65% of sessions included meaningful interaction.
GA4 made this the default metric (replacing bounce rate) because it's more honest. Under the old definition, someone who read your entire landing page for 5 minutes but didn't click anything counted as a "bounce." Under engagement rate, they count as engaged if they stayed 10+ seconds. That's a fundamentally better measurement for content-heavy landing pages.
What engagement rate tells you
A low engagement rate (under 50%) means most visitors aren't even giving your page a chance. They're leaving within 10 seconds without interacting. That points to a first-impression problem: slow loading, confusing hero section, or a mismatch between what they expected and what they found. Fix these before worrying about CTA copy or pricing strategy.
A high engagement rate (70%+) with low conversion rate tells a different story: visitors are interested and interactive but something stops them from converting. That's usually a value proposition gap, pricing objection, or trust issue. Different diagnosis, different fix. Engagement rate helps you distinguish between "they didn't care" and "they cared but weren't convinced."