DataSag guides · Updated 27 October 2026

Fix duplicate analytics pageviews on Gatsby

Multiple tracking requests do not necessarily mean duplicate pageviews. DataSag sends pageviews, scroll milestones, engagement updates and custom events. Inspect eventName before removing code. This guide applies to Gatsby.

Start with the Gatsby installation

Use the Gatsby SSR onRenderBody API to add one deferred external script through setHeadComponents. Merge the addition into an existing hook rather than overwriting it, and keep the React import required by your file format. Build and publish the generated site; inspect its HTML because this hook concerns generated documents.

A browser onRouteUpdate hook, a plugin and gatsby-ssr can all add analytics behavior. Do not add a second pageview sender without testing the current tracker. gatsby develop is not a substitute for checking generated production documents.

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 duplicate analytics pageviews in Gatsby

  1. Inventory gatsby-ssr head components, gatsby-browser hooks, page components and analytics plugins. One plugin can add a tracker while another route hook reports the same pageview.
  2. Keep one intended loader and verify the current tracker route behavior before retaining onRouteUpdate pageview code. Preserve unrelated Gatsby hooks and head components when changing the installation.
  3. Build and publish, then test direct entry, a Gatsby Link and Back. Classify eventName before counting pageviews and inspect repeated visits for additional listeners left by a page component loader.

The built Gatsby app has one global installation and no overlapping browser hook for the same supported pageview.

Complete the collection checks

  1. Open Network and filter /api/track. Reload once without clicking or scrolling. Inspect eventName in each payload: null identifies a pageview; scroll, click_heatmap and __datasag_engagement are other records.
  2. Count rendered script elements with data-datasag-key. There should be one intended installation for this project. Search your code, site header settings, embeds and tag manager for additional copies.
  3. Remove redundant script insertion mechanisms, keeping the site-wide installation. Two copies execute independently even when their browser download is cached.
  4. Check for custom router listeners that manually send pageviews. The current tracker handles pushState, replaceState and popstate and ignores a repeated pathname. Do not add a second pageview implementation without a demonstrated gap.
  5. Repeat a direct load, a second route and browser Back. Correlate pageview records with actual path changes. A query-only change on the same pathname is not a new pageview in the current tracker.
[...document.querySelectorAll('script[data-datasag-key]')]
  .map(script => ({
    src: script.src,
    key: script.getAttribute('data-datasag-key')
  }));

What a successful check looks like

A single installation and one pageview dispatch for each actual pathname change in the tested sequence. Additional engagement records remain available.

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

Comparing the total number of events with the number of pageviews produces a false duplicate diagnosis. Keep the event categories separate throughout the check.

Installation snippet for Gatsby

The shared installation belongs in an onRenderBody head component in the root gatsby-ssr.js file. Use this as the installation reference while checking the procedure above.

const React = require("react");

// Merge into your existing onRenderBody hook if one exists.
exports.onRenderBody = ({ setHeadComponents }) => {
  setHeadComponents([
    <script key="datasag" defer
      src="https://www.datasag.com/tracker.js"
      data-datasag-key="YOUR_PUBLIC_KEY" />
  ]);
};

Related Gatsby guides

Full Gatsby setup guide · Search and AI visibility

References

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