# Add CLItrail to Next.js (Pages Router)
Where the CLItrail tag goes in Next.js (Pages Router), in its own idiom, with the consent, CSP and client-side routing details and how to check it works.
Written for Next.js 16 (the same code works from 12.2)
## Where the tag goes
Edit `pages/_app.tsx`. Put the tag on every page that shows your install command; site-wide is best, after your existing analytics tags.
```js
import type { AppProps } from 'next/app';
import Script from 'next/script';
export default function App({ Component, pageProps }: AppProps) {
return (
<>
);
}
```
## Only after consent
Use the loader in place of the tag: nothing from CLItrail loads until `startClitrail()` runs. Load the loader before your consent manager's script and call `startClitrail()` from the manager's accept callback (most managers also run it on later visits once a choice is stored; check yours). Use the marketing category when installs go to Google Ads, Meta, TikTok or X Ads, and the analytics category when they only reach GA4 or your webhooks. In the Pages Router, `beforeInteractive` scripts go in `pages/_document.tsx`; drop the Script from `_app.tsx` when you gate on consent.
Consent loader
```js
// Loads CLItrail only after the visitor agrees. Call startClitrail() from your
// consent manager's "accepted" callback; nothing is fetched or stored before that.
window.startClitrail = () => {
if (document.getElementById('clitrail')) return;
const tag = document.createElement('script');
tag.id = 'clitrail';
tag.src = 'https://YOUR_SERVICE/browser.js';
tag.dataset.website = 'YOUR_WEBSITE_ID';
document.head.append(tag);
};
```
```js
import { Html, Head, Main, NextScript } from 'next/document';
import Script from 'next/script';
export default function Document() {
return (