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Meta Pixel

Load the Meta Pixel only after visitors allow marketing, and send each choice through fbq consent grant and revoke.

Inth keeps the consent record of each choice, with the visitor’s country and the policy that applied.

Start for free
pnpm add @c15t/integrations
Meta PixelWaiting for consent
Before a choice

fbevents.js does not load, and window.fbq does not exist.

Turn the switch on, then off, to see what loads.

Before you start

You need an Inth project that connects to your app, c15t in that app and your pixel ID from Meta Events Manager.

New to c15t? Complete the quickstart for your framework first. Keep its Inth endpoint, policy, styles and consent UI.

Open the quickstart for your framework

How consent gets to the Meta Pixel

Before marketing has permission, the c15t metaPixel helper defines no fbq function and loads nothing from Meta.

After permission, the helper queues fbq('consent', 'grant'), init and PageView. Then it loads fbevents.js.

On withdrawal, the helper keeps the pixel and calls fbq('consent', 'revoke'). If the visitor allows marketing again before the reload, it calls grant again.

Installation

The Meta Pixel has one load mode in c15t. The helper waits for marketing permission.

Wait for permission. No request goes to Meta until the visitor accepts marketing. On withdrawal, the pixel gets fbq('consent', 'revoke').

metaPixel({ pixelId })

An opt-out policy or no policy gives optional categories permission before a choice. Then the Meta Pixel loads on the first page. This guide uses an opt-in policy.

Setup steps

  1. Install the integration package

    Add the helpers next to c15t. An import alone does not start the Meta Pixel.

    pnpm add @c15t/integrations
  2. Add your pixel ID

    The helper sends the page view of the pixel. Events from your code need a permission check of their own.

    src/consent-scripts.ts
    import { metaPixel } from '@c15t/integrations/meta-pixel';
    
    export const scripts = [metaPixel({ pixelId: '123456789012345' })];

    The package also exports metaPixelEvent and other typed wrappers. They do not check permission, so check it before each call.

  3. Check permission before each event

    window.fbq still exists after withdrawal. So check the current marketing permission first, for example with useConsent('marketing') in React.

    src/track-purchase.ts
    export function trackPurchase(marketingAllowed: boolean, value: number) {
      if (!marketingAllowed || typeof window.fbq !== 'function') return;
      window.fbq('track', 'Purchase', { currency: 'USD', value });
    }
  4. Register it with your existing setup

    Add scripts to the c15t configuration that you have now. Keep your Inth endpoint, mode, policy, styles and consent UI.

    Add scripts to c15t.config.ts, next to next.config.ts. Keep the rest of your config, such as mode, in the same call. App Router, Pages Router and static export read the same file.

    c15t.config.ts
    import { defineConsentConfig } from 'c15t/next';
    import { scripts } from './src/consent-scripts';
    
    export default defineConsentConfig({ scripts });

    Pass scripts to the ConsentRoot in your root route. Import helpers in the route module, not in a server function: script configurations carry callbacks.

    src/routes/__root.tsx
    import { scripts } from '../consent-scripts';
    
    <ConsentRoot state={consent} scripts={scripts}>

    Add scripts to the options of your ConsentProvider, next to mode. Keep the banner, dialog and preferences link inside the provider.

    src/consent.tsx
    import { scripts } from './consent-scripts';
    
    <ConsentProvider options={{ mode, scripts }}>

    Register scripts under the c15t key in app.config.ts. Keep them out of nuxt.config.ts, which reaches the browser as JSON and drops the helper callbacks.

    app/app.config.ts
    import { scripts } from '../src/consent-scripts';
    
    export default defineAppConfig({
      c15t: { scripts },
    });

    Pass scripts to the c15tVue plugin call you have now. The plugin starts one script loader when the app mounts.

    src/main.ts
    import { c15tVue, manifest } from 'c15t/vue/vue-plugin';
    import { scripts } from './consent-scripts';
    
    app.use(c15tVue, {
      mode: manifest(),
      scripts,
    });

    Add scripts to the client entrypoint, which the integration finds on its own. Keep helpers out of astro.config.mjs: its options are serialized into the page.

    src/c15t.client.ts
    import type { C15tClientOptionsExtension } from 'c15t/astro';
    import { scripts } from './consent-scripts';
    
    export default { scripts } satisfies C15tClientOptionsExtension;

    Pass scripts as a prop to the ConsentProvider you have now. The provider owns the loader and disposes it on unmount.

    src/App.svelte
    <script lang="ts">
      import { ConsentProvider, manifest } from 'c15t/svelte';
      import { scripts } from './consent-scripts';
    </script>
    
    <ConsentProvider mode={manifest()} {scripts}>
      <!-- Your app and consent UI -->
    </ConsentProvider>

    Add scripts to the ConsentRoot in the root layout. Import helpers in the layout component, not in +layout.server.ts: a server load cannot send functions to the browser.

    src/routes/+layout.svelte
    <script lang="ts">
      import { ConsentRoot } from 'c15t/svelte';
      import { scripts } from '../consent-scripts';
    
      let { children, data } = $props();
    </script>
    
    <ConsentRoot state={data.consent} {scripts}>
      {@render children()}
    </ConsentRoot>

    Paste the vendor’s snippet behind consent

    The helpers need a bundler. On a page with the c15t script tag, paste the vendor’s own snippet instead and keep it inert until visitors allow its category. Helper options, such as loadMode, do not apply.

    index.html
    <script type="text/plain" data-c15t-category="marketing">
      // The vendor's snippet, unchanged
    </script>

    Pass scripts to init() from @c15t/browser, next to your mode. With createConsentRuntime, pass scripts to it instead.

    src/consent.ts
    import { init, manifest } from '@c15t/browser';
    import { scripts } from './consent-scripts';
    
    const consent = init({
      mode: manifest(),
      scripts,
    });
All frameworks

Remove the original pixel snippet, its noscript image and each tag manager entry for the same pixel.

Verify your setup

Use a private window with an opt-in policy. Open DevTools Network and filter by facebook. Then test the three states.

  • Before a choice

    fbevents.js does not load, and window.fbq does not exist.

  • After you allow marketing

    fbevents.js loads, and a request to facebook.com/tr carries ev=PageView. A guarded event sends its own tr request.

  • After you withdraw marketing

    Before the reload, trackPurchase sends nothing. After the reload, the pixel stays blocked.

With client side navigation, make sure that each route change sends one page view, not two.

Open the full Meta Pixel guide