Setting up Facebook Pixel via GTM for WordPress/WooCommerce + CAPI + Deduplication

🧾 Technical Specification: Setting up Facebook Pixel via GTM for WordPress/WooCommerce + CAPI + Deduplication

📌 Project Description

It is necessary to set up a complete and correct integration of Facebook Pixel through Google Tag Manager (GTM), including:

• Tracking all key events (from site entry to purchase)

• Connecting server-side event transmission (CAPI)

• Deduplication of events between browser and server

• Connecting all possible client parameters (Advanced Matching)

• Accounting for all UTM and Click ID (fbclid, gclid etc.)

• The site runs on WordPress + WooCommerce + Elementor

✅ What has already been done

• The plugin PixelYourSite (PYS) is installed

• Multiple attempts have been made to configure, but:

  • CAPI works, but events are duplicated

  • Browser events are not always transmitted correctly

  • eventID does not match, Facebook considers events different

🎯 Task Goals

1. Completely abandon PYS if it interferes with GTM operation.

2. Configure Facebook Pixel via GTM, manually, without conflicts.

3. Connect Conversion API (CAPI) via GTM Server Side or through a plugin if appropriate.

4. Implement deduplication: transmit the same eventID both in browser and on the server.

5. Transmit all client parameters:

   • Name

   • Email

   • Phone

   • City, ZIP

   • External ID

   • (advanced matching)

6. Configure transmission of all order parameters (amount, currency, list of products).

7. Ensure that no duplicates occur, and events in Events Manager are displayed with the label "Server + Browser".

🧰 Technical Implementation Requirements

• Configure all tags in Google Tag Manager (GTM)

• Use Data Layer in WooCommerce

• Connect Facebook Pixel via custom HTML tag with full control

• Transmit eventID manually or generate it in advance and synchronize between browser and CAPI

• Configure GTM at all stages:

  • PageView

  • ViewContent

  • AddToCart

  • InitiateCheckout

  • Purchase

• Verify proper operation using Facebook Pixel Helper and Events Manager

• 
  

• ⚠️ Important

  • The site uses two different classes for "Add to Cart" buttons:

    • On the category page

    • On the single product page

• ⚙️ Implement tracking of AddToCart via tracking by classes or data-attributes of both buttons, with transmission of the same eventID (via JS and Data Layer if needed).

⚙️ Platform:

• WordPress + WooCommerce

• Elementor (all pages built with Elementor)

• FunnelKit (used for funnel and thank you page)

• Hosting: LiteSpeed

❗Important:

• It is necessary to prevent event duplication

• All events should be transmitted both from browser and server with the same eventID

• Avoid solutions that conflict with GTM

• Testing period: until full stable operation