pixel-capi-auditor

name	pixel-capi-auditor
description	Audit pixel and Conversions API (CAPI) implementations across all ad platforms. Use when verifying tracking setup, diagnosing conversion data discrepancies, optimizing Event Match Quality, or auditing deduplication logic.

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

Check	How to Verify	Pass Criteria
Pixel installed	Meta Pixel Helper extension	Pixel fires on all pages
Base code present	View page source → search "fbq"	fbq('init', 'PIXEL_ID') found
PageView fires	Pixel Helper → PageView event	Fires on every page load
Standard events	Pixel Helper → event list	Purchase, Lead, AddToCart as needed
CAPI events	Events Manager → Test Events	Server events appear
Deduplication	Events Manager → event details	event_id matches pixel + CAPI
EMQ score	Events Manager → Event Overview	Score ≥ 6.0 (Good)
Domain verification	Business Settings → Brand Safety	Domain verified
iOS 14+ setup	Events Manager → AEM	8 events configured, prioritized

Event Match Quality (EMQ) Optimization

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

EMQ Score	Rating	Impact on Attribution
0-3	Poor	Significant attribution loss (30-50%)
3-5	Fair	Moderate attribution loss (15-30%)
5-7	Good	Minor attribution loss (5-15%)
7-9	Great	Minimal loss (< 5%)
9-10	Excellent	Near-perfect matching

Parameters that improve EMQ (in order of impact):

Parameter	EMQ Impact	Implementation
em (email, hashed)	+3-4 points	SHA-256 hash of lowercase, trimmed email
ph (phone, hashed)	+1-2 points	SHA-256 hash of digits only (with country code)
fn + ln (name, hashed)	+1 point	SHA-256 hash of lowercase first/last name
external_id	+1 point	Your internal user ID (hashed)
fbp (browser ID)	+1-2 points	_fbp cookie value
fbc (click ID)	+2-3 points	_fbc cookie value or fbclid from URL
client_ip_address	+0.5 points	User's IP (not server IP)
client_user_agent	+0.5 points	Browser user agent string

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:

Symptom	Cause	Fix
Double-counted conversions	Missing event_id on pixel or CAPI	Add event_id to both
Conversion count too low	event_id mismatched (different format)	Ensure identical string on both
Intermittent doubles	Race condition, CAPI fires before pixel	Use same server-generated ID
CAPI events not matching	Wrong event_name casing	Use exact standard event names

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

Check	How to Verify	Pass Criteria
Conversion tracking tag	GTM → Tags → Google Ads Conversion	Tag fires on conversion page
Enhanced conversions	Tag settings → Enhanced conversions	Enabled with user data
Consent mode	GTM → Consent Overview	ad_storage and analytics_storage configured
Conversion linker	GTM → Tags → Conversion Linker	Fires on all pages
GCLID parameter	Landing page URL	gclid captured and stored
Server-side tagging	GTM → Server container	Optional but recommended

Enhanced Conversions Setup

Method 1: Google tag (gtag.js)

gtag('set', 'user_data', {
  "email": "[e-mail]",  // Hashed automatically
  "phone_number": "[phone]",
  "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:

Signal	Purpose	Default (no consent)
ad_storage	Google Ads cookies	denied
ad_user_data	Sending user data to Google	denied
ad_personalization	Remarketing	denied
analytics_storage	GA4 cookies	denied

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

Check	How to Verify	Pass Criteria
Pixel installed	TikTok Pixel Helper extension	Pixel fires on pages
Base code	View source → search "ttq"	ttq.load('PIXEL_CODE') found
Standard events	Pixel Helper → event list	CompleteRegistration, Purchase, etc.
Events API	Events Manager → Diagnostics	Server events arriving
Match quality	Events Manager → Match Rate	≥ 50% match rate
ttclid capture	URL parameter check	Captured and stored in cookie

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

Check	How to Verify	Pass Criteria
Insight Tag	View source → search "linkedin"	_linkedin_partner_id or tag present
Partner ID	LinkedIn Campaign Manager → Analyze	Matches installed tag
Conversion tracking	Campaign Manager → Conversions	Events configured
CAPI setup	API test call	Events accepted
li_fat_id capture	Cookie check	First-party cookie stored

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

Check	How to Verify	Pass Criteria
Reddit Pixel	View source → search "rdt"	rdt('init', 'PIXEL_ID') found
PageVisit event	Pixel fires	rdt('track', 'PageVisit') on all pages
rdt_cid capture	URL parameter	Reddit click ID stored in cookie
_rdt_uuid cookie	Cookie check	UUID cookie present
CAPI events	Reddit Events Manager	Server events in diagnostics

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

Check	How to Verify	Pass Criteria
UET tag	View source → search "bat.bing.com"	UET tag fires
Tag ID	Microsoft Ads → Conversion Tracking	Matches installed tag
msclkid auto-tagging	URL parameter check	Enabled in account settings
Offline conversions	API test call	Events accepted
Revenue tracking	Conversion goal settings	Revenue values reported

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

Platform	URL Parameter	Cookie Name	Lifetime
Meta	fbclid	_fbc, _fbp	90 days, 2 years
Google	gclid	_gcl_aw	90 days
TikTok	ttclid	_ttp	13 months
LinkedIn	li_fat_id	li_fat_id	30 days
Reddit	rdt_cid	_rdt_uuid	90 days
Microsoft	msclkid	_uetmsclkid	90 days
X (Twitter)	twclid	N/A	Session

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:

Platform	Pixel	CAPI	Dedup	EMQ/Match	Action Needed
Meta	✅	✅	❌	4.2	Add event_id, email hash
Google	✅	⚠️	✅	N/A	Enable enhanced conversions
TikTok	✅	❌	N/A	N/A	Implement Events API
LinkedIn	❌	❌	N/A	N/A	Install Insight Tag + CAPI
Reddit	✅	❌	N/A	N/A	Implement CAPI
Microsoft	✅	❌	N/A	N/A	Enable auto-tagging + offline

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

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