Missing pageleave events

The missing pageleave events check fires when your project sends $pageview events but no $pageleave events. PostHog uses the pair to measure how long people stay on a page.

What this check looks for

Once a day, the check looks back over the last 30 days. If it sees $pageview events but zero $pageleave events, it raises a warning.

Why it matters

Missing $pageleave breaks bounce rate, session duration, and scroll-depth metrics in web analytics. It usually means pageleave capture is disabled in the SDK, so these reports will be empty or wrong even though pageviews look fine.

Fix it manually

The fix is almost always on the SDK side:

1. Open the Web analytics health page.
2. Make sure you're on a recent posthog-js with pageview autocapture enabled – it emits $pageleave automatically when someone navigates away.
3. If you capture pageviews manually (capture_pageview: false), add a matching $pageleave capture on route changes and page unload.

Fix it automatically with the Inbox and PostHog Code

With the Inbox and health checks enabled as a signal source, the agent will:

• Confirm the gap in your data ($pageview events present, $pageleave absent).
• Locate your posthog.init call and ensure pageview autocapture is enabled.
• If pageviews are captured manually, add a matching $pageleave capture on navigation.
• Open a PR.

The issue resolves on the next run once $pageleave events arrive.

Related

• Health checks overview
• Configuring pageview and pageleave capture
• Missing web vitals