Fix DataSag analytics not working on Next.js Pages Router

Start with the Next.js Pages Router installation

Import Script from next/script in pages/_app.tsx. Keep Component and pageProps, and add the tracker once alongside the page component. The shared app stays mounted as users navigate between pages.

Do not install the same tracker in both _app and _document. Do not attach another pageview sender to router.events before testing the tracker's built-in History API handling.

Use the public project key from the DataSag project you are inspecting. A test on a preview domain does not confirm that the production domain has the same code or settings.

Fix DataSag analytics not working in Next.js Pages Router

1. Check that pages/_app.tsx is the custom app used by the deployed project. Preserve the Component render when adding Script. A snippet inside a rarely used page does not cover the rest of the Pages Router site.
2. Compare the script in _app with any installation in _document, a tag manager, or a third-party analytics component. Find the rendered element and key on the affected production page before changing event code.
3. If only a named action is missing, inspect its browser success handler. API routes and getServerSideProps do not run in the visitor browser and cannot call window.datasag. Test the action after the Script has loaded.

The missing boundary is traced to app coverage, browser script execution, or the action handler that can actually observe success.

Complete the collection checks

1. Confirm the change reached the public domain. Inspect the live HTML and clear only caches that serve the old document. A saved editor change may still need publishing.
2. Check that tracker.js exists in the Network panel and that the script contains the public key from the same DataSag project you are viewing.
3. Check whether your test browser is excluded with datasag_ignore. Restore inclusion with ?datasag_ignore=false only if this browser should count. Respect any consent controls configured on your site.
4. Inspect the browser Console for Content Security Policy or script errors. Check /api/track request responses: 400 indicates invalid input, 404 can indicate an unknown project key, and a server failure needs investigation rather than repeated snippet changes.
5. Try a controlled browser profile to identify an extension block. Do not bypass a visitor's privacy preferences. Then check the project's selected date range, path and domain.
6. Collect the affected public URL, approximate time, request status and installation location for support. Omit account credentials and visitor data from screenshots.

typeof window.datasag?.track
// If undefined, first investigate whether the script executed.

new URL(location.href).searchParams.get('datasag_ignore')
// Also check for a previously saved browser exclusion.

What a successful check looks like

The first failed boundary is identified and corrected, and a new controlled visit reaches the right project. The browser Console and Network panel provide the evidence.

Record the public path you tested, the browser state, the approximate time and the observed request. Check one direct page load and one later navigation so the result covers more than the homepage.

Common mistake

Do not replace the public project key with a Supabase, Stripe or provider secret. The browser snippet uses only the project's public tracking key.

Installation snippet for Next.js Pages Router

The shared installation belongs in pages/_app.tsx, alongside the page component. Use this as the installation reference while checking the procedure above.

import Script from "next/script";

// Alongside <Component {...pageProps} /> in pages/_app.tsx:
<Script
  id="datasag"
  src="https://www.datasag.com/tracker.js"
  data-datasag-key="YOUR_PUBLIC_KEY"
  strategy="afterInteractive"
/>

Related Next.js Pages Router guides

• Verify DataSag analytics
• Fix duplicate analytics pageviews
• Track custom events
• Track UTM campaigns
• Measure AI referral traffic
• Configure CSP for DataSag analytics
• Exclude your own analytics visits
• Load analytics without blocking rendering

Full Next.js Pages Router setup guide · Search and AI visibility

References

Official Next.js Pages Router documentation covers the integration point. For DataSag data handling, read the privacy policy. Use support if a request fails after these checks.