Pixel & CAPI Auditor

Comprehensive audit framework for client-side pixels and server-side Conversions APIs across Meta, Google, TikTok, LinkedIn, Reddit, and Microsoft Ads. Covers setup verification, Event Match Quality optimization, deduplication validation, and diagnostic commands.

Capabilities

1. Meta Pixel + CAPI Audit - Verify Pixel firing, CAPI events, EMQ scores, and deduplication
2. Google Enhanced Conversions Audit - Validate enhanced conversion setup and consent mode
3. TikTok Events API Audit - Check pixel and server-side event configuration
4. LinkedIn Insight Tag + CAPI Audit - Verify tag installation and conversion API
5. Reddit CAPI Audit - Validate Reddit pixel and server-side tracking
6. Microsoft UET + Offline Conversions - Audit Universal Event Tracking and offline uploads
7. Cross-Platform Deduplication - Ensure events aren't double-counted

Meta Pixel + Conversions API

Audit Checklist

Event Match Quality (EMQ) Optimization

What is EMQ? A 0-10 score measuring how well Meta can match server events to Facebook users.

Parameters that improve EMQ (in order of impact):

CAPI event payload for maximum EMQ:

{
  "data": [{
    "event_name": "Purchase",
    "event_time": 1706745600,
    "event_id": "evt_unique_123",
    "event_source_url": "https://example.com/thank-you",
    "action_source": "website",
    "user_data": {
      "em": ["a1b2c3...sha256..."],
      "ph": ["d4e5f6...sha256..."],
      "fn": ["ab12cd...sha256..."],
      "ln": ["ef34gh...sha256..."],
      "external_id": ["user_789_hashed"],
      "fbc": "fb.1.1706745600.ABCdef",
      "fbp": "fb.1.1706745600.1234567890",
      "client_ip_address": "203.0.113.1",
      "client_user_agent": "Mozilla/5.0..."
    },
    "custom_data": {
      "value": 99.99,
      "currency": "USD",
      "content_ids": ["SKU-123"],
      "content_type": "product",
      "num_items": 1
    }
  }]
}

Deduplication Setup Verification

How deduplication works: Both pixel and CAPI send the same event. Meta deduplicates using event_id + event_name. If both have the same event_id, only one is counted.

Verification steps:

1. Generate a unique event_id on the server at conversion time:

   event_id = "evt_" + UUID or transaction_id

2. Pass to both pixel and CAPI:
   • Pixel: fbq('track', 'Purchase', {value: 99.99}, {eventID: 'evt_abc123'})
   • CAPI: "event_id": "evt_abc123" in the server payload
3. Verify in Events Manager:
   • Go to Events Manager → Test Events
   • Trigger a test conversion
   • Check that event appears once (not twice)
   • Click event → "Match Quality" should show "Deduplicated"

Common deduplication failures:

Diagnostic Commands

Test CAPI endpoint:

curl -X POST "https://graph.facebook.com/v21.0/PIXEL_ID/events?access_token=TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "data": [{
      "event_name": "PageView",
      "event_time": '$(($(date +%s)))',
      "event_id": "test_'$(uuidgen)'",
      "action_source": "website",
      "event_source_url": "https://example.com",
      "user_data": {
        "client_ip_address": "1.2.3.4",
        "client_user_agent": "test"
      }
    }],
    "test_event_code": "TEST12345"
  }'

Check pixel on website:

curl -s "https://example.com" | grep -oP 'fbq\([^)]+\)' | head -20

Verify domain:

curl -s "https://example.com" | grep -oP 'meta-tag.*facebook-domain-verification'

Google Enhanced Conversions

Audit Checklist

Enhanced Conversions Setup

Method 1: Google tag (gtag.js)

gtag('set', 'user_data', {
  "email": "user@example.com",  // Hashed automatically
  "phone_number": "+11234567890",
  "address": {
    "first_name": "John",
    "last_name": "Doe",
    "street": "123 Main St",
    "city": "New York",
    "region": "NY",
    "postal_code": "10001",
    "country": "US"
  }
});

Method 2: GTM with CSS selectors

1. Tag → Google Ads Conversion Tracking
2. Enable "Include user-provided data from your website"
3. Configure CSS selectors for email, phone, name, address fields
4. Test with GTM Preview mode

Method 3: Enhanced Conversions API (server-side)

curl -X POST "https://googleads.googleapis.com/v17/customers/CUSTOMER_ID:uploadConversionAdjustments" \
  -H "Authorization: Bearer ACCESS_TOKEN" \
  -H "developer-token: DEV_TOKEN" \
  -d '{
    "conversionAdjustments": [{
      "adjustmentType": "ENHANCEMENT",
      "conversionAction": "customers/CUSTOMER_ID/conversionActions/ACTION_ID",
      "adjustmentDateTime": "2026-01-15 12:00:00-05:00",
      "orderId": "ORDER-123",
      "userIdentifiers": [{
        "hashedEmail": "a1b2c3...sha256..."
      }]
    }]
  }'

Consent Mode v2

Required signals for EEA/UK:

Implementation:

// Before gtag/GTM loads:
window.dataLayer = window.dataLayer || [];
function gtag(){dataLayer.push(arguments);}
gtag('consent', 'default', {
  'ad_storage': 'denied',
  'ad_user_data': 'denied',
  'ad_personalization': 'denied',
  'analytics_storage': 'denied',
  'wait_for_update': 500
});

// After user grants consent:
gtag('consent', 'update', {
  'ad_storage': 'granted',
  'ad_user_data': 'granted',
  'ad_personalization': 'granted',
  'analytics_storage': 'granted'
});

TikTok Events API

Audit Checklist

Events API Payload

{
  "pixel_code": "PIXEL_CODE",
  "event": "CompletePayment",
  "event_id": "evt_unique_456",
  "timestamp": "2026-01-15T12:00:00-05:00",
  "context": {
    "ad": {
      "callback": "ttclid_value_from_url"
    },
    "page": {
      "url": "https://example.com/thank-you",
      "referrer": "https://example.com/checkout"
    },
    "user": {
      "external_id": "user_789_sha256",
      "email": "sha256_hashed_email",
      "phone_number": "sha256_hashed_phone"
    },
    "user_agent": "Mozilla/5.0...",
    "ip": "203.0.113.1"
  },
  "properties": {
    "value": 99.99,
    "currency": "USD",
    "contents": [{"content_id": "SKU-123", "quantity": 1, "price": 99.99}],
    "content_type": "product"
  }
}

Endpoint:

curl -X POST "https://business-api.tiktok.com/open_api/v1.3/event/track/" \
  -H "Content-Type: application/json" \
  -H "Access-Token: SERVER_ACCESS_TOKEN" \
  -d '{ ... payload ... }'

LinkedIn CAPI

Audit Checklist

LinkedIn CAPI Payload

{
  "conversion": "urn:lla:llaPartnerConversion:CONVERSION_RULE_ID",
  "conversionHappenedAt": 1706745600000,
  "conversionValue": {
    "currencyCode": "USD",
    "amount": "99.99"
  },
  "eventId": "evt_unique_789",
  "user": {
    "userIds": [
      {
        "idType": "SHA256_EMAIL",
        "idValue": "sha256_hashed_email"
      },
      {
        "idType": "LINKEDIN_FIRST_PARTY_ADS_TRACKING_UUID",
        "idValue": "li_fat_id_value"
      }
    ],
    "userInfo": {
      "firstName": "John",
      "lastName": "Doe",
      "companyName": "Acme Inc",
      "title": "VP Marketing",
      "countryCode": "US"
    }
  }
}

Endpoint:

curl -X POST "https://api.linkedin.com/rest/conversionEvents" \
  -H "Authorization: Bearer ACCESS_TOKEN" \
  -H "LinkedIn-Version: 202510" \
  -H "X-Restli-Protocol-Version: 2.0.0" \
  -H "Content-Type: application/json" \
  -d '{"elements": [{ ... payload ... }]}'

Reddit CAPI

Audit Checklist

Reddit CAPI Payload

{
  "events": [{
    "event_at": "2026-01-15T12:00:00Z",
    "event_type": {
      "tracking_type": "Purchase"
    },
    "click_id": "rdt_cid_value",
    "event_metadata": {
      "item_count": 1,
      "value_decimal": 99.99,
      "currency": "USD",
      "conversion_id": "evt_unique_012"
    },
    "user": {
      "email": "sha256_hashed_email",
      "external_id": "user_789",
      "uuid": "_rdt_uuid_value",
      "ip_address": "203.0.113.1",
      "user_agent": "Mozilla/5.0..."
    }
  }]
}

Endpoint:

curl -X POST "https://ads-api.reddit.com/api/v2.0/conversions/events/PIXEL_ID" \
  -H "Authorization: Bearer CAPI_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{ ... payload ... }'

Microsoft UET + Offline Conversions

Audit Checklist

Offline Conversions Payload

{
  "offlineConversions": [{
    "conversionName": "Purchase",
    "conversionTime": "2026-01-15T12:00:00.000Z",
    "conversionValue": 99.99,
    "conversionCurrencyCode": "USD",
    "microsoftClickId": "msclkid_value",
    "hashedEmailAddress": "sha256_hashed_email",
    "hashedPhoneNumber": "sha256_hashed_phone"
  }]
}

Cross-Platform Deduplication Strategy

Click ID Capture Matrix

Middleware Implementation

Capture all click IDs in a single middleware:

On every request:
  1. Check URL params for: fbclid, gclid, ttclid, li_fat_id, rdt_cid, msclkid, twclid
  2. Store each found ID in a first-party cookie
  3. On conversion event, read all cookies
  4. Send to each platform's CAPI with matching click ID
  5. Use single event_id/conversion_id for deduplication

Unified Conversion Event

When a conversion happens, fire to all platforms simultaneously:

Event: Purchase ($99.99)
event_id: "evt_txn_abc123"

→ Meta CAPI: event_id="evt_txn_abc123", fbc="{_fbc}", fbp="{_fbp}"
→ Google Enhanced Conversions: order_id="ORDER-123", gclid="{gclid}"
→ TikTok Events API: event_id="evt_txn_abc123", ttclid="{ttclid}"
→ LinkedIn CAPI: eventId="evt_txn_abc123", li_fat_id="{li_fat_id}"
→ Reddit CAPI: conversion_id="evt_txn_abc123", click_id="{rdt_cid}"
→ Microsoft Offline: microsoftClickId="{msclkid}"

Examples

Example 1: Meta EMQ Improvement

Before: EMQ Score 3.2 (Poor)

• Only sending: client_ip_address, client_user_agent
• Missing: email, phone, fbp, fbc

After adding all parameters: EMQ Score 8.1 (Great)

• Added: hashed email (+3.5), fbp cookie (+1.0), fbc cookie (+0.5)
• Attributed conversions increased 42%
• CPA decreased 28% (Meta could optimize with better data)

Example 2: Deduplication Fix

Symptom: Google Ads reporting 200 conversions, GA4 reporting 130.

Root cause: Enhanced conversions firing without order_id, so duplicate events from gtag + server-side upload counted twice.

Fix: Added transaction_id / order_id to both gtag conversion tag and server-side upload. Google deduplicates on order_id.

Result: Google Ads now reports 135 conversions (matches GA4 within 4%).

Example 3: Full Multi-Platform Audit

Audit results for an e-commerce site:

Priority order: Meta CAPI fix → Google Enhanced → TikTok CAPI → LinkedIn full setup → Reddit CAPI → Microsoft offline

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