NextJS - Google Analytic code

aizu

File: _app.js

import Script from "next/script";
import Head from "next/head"

const GA_MEASUREMENT_ID = 'G-XXXXXXXX'

<Head>
<Script
  src={`https://www.googletagmanager.com/gtag/js?id=${GA_MEASUREMENT_ID}`}
  strategy="afterInteractive"
/>
<Script id="google-analytics" strategy="afterInteractive">
  {`
    window.dataLayer = window.dataLayer || [];
    function gtag(){window.dataLayer.push(arguments);}
    gtag('js', new Date());
    gtag('config', '${GA_MEASUREMENT_ID}');
  `}
</Script>
</Head>

Ref: https://hackernoon.com/setting-up-google-analytics-4-in-a-nextjs-project