What is the difference between the Meta Pixel and the Conversions API?

The pixel runs in the shopper's browser, so ad blockers and browser privacy settings can stop it. The Conversions API sends the same events from your server to Meta's. Run both together with a shared event ID so Meta keeps one copy of each event.

How do I set up the Facebook Conversions API?

On Shopify, open the Facebook & Instagram sales channel, go to Data sharing settings and set customer data sharing to Enhanced or Maximum. Other platforms have similar partner integrations. Without one, use Meta's Conversions API Gateway or a direct server integration, then check deduplication in Events Manager.

How do I connect my CRM to Meta's Conversions API?

Use Meta's Conversions API for CRM to send lead stages from your CRM back to Meta. It works with Facebook and Instagram lead ads, needs the Meta lead ID stored in your CRM, and Meta asks for at least 200 leads a month and daily uploads before you optimize for conversion leads.

What is a Meta CAPI audit?

A structured review of the Meta Conversions API setup: deduplication with the pixel, event match quality, parameter coverage, funnel completeness, and reconciliation against real sales, so Meta learns from clean signal.

Why are my Meta conversions double-counted?

Usually the pixel and Conversions API are not sharing an event ID, so Meta counts the browser and server versions of the same event separately. Add a shared event ID to enable deduplication.

What is event match quality?

Meta's score of how well it can match your events to people, based on customer parameters like hashed email and phone. Low match quality weakens attribution and optimization.

Why does Meta report more revenue than my store?

Meta counts view-through and cross-device conversions generously, so its number usually overstates contribution. Reconcile against source-of-truth sales before making budget decisions.

Workflowadvanced

Meta Conversions API: how to set it up and audit it

Symptom: Meta is under-reporting conversions and event quality looks weak

TL;DR

The Meta Conversions API (CAPI) sends conversion events from your server to Meta, alongside the browser pixel, so Meta still sees purchases and leads when the pixel is blocked. The Meta Conversions API keeps conversion signal flowing when the browser pixel is blocked, but a sloppy setup double-counts, matches poorly, or sends thin events. This workflow audits deduplication, event match quality, parameter coverage, and reconciliation against real sales, so Meta's algorithm learns from clean, complete signal rather than a leaky or inflated one.

Time

2 to 4 hours

Difficulty

Advanced

Impact

Clean, complete Meta signal

How often

Quarterly, and after changes

Written by

Pankaj

Google Ads Strategist

Updated October 12, 2026Reviewed by Eric Mascarenhas

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Prerequisites

Meta Business Manager and Events Manager access
Knowledge of the current pixel and CAPI setup
Access to the source-of-truth sales data
The event parameters currently being sent

1
Confirm how the Conversions API is connected
Before auditing, find out how events reach the Conversions API, because each setup fails in different places. A partner integration is the usual route for stores: on Shopify, the Facebook & Instagram app turns on the Conversions API when customer data sharing is set to Enhanced or Maximum (Sales channels, Facebook & Instagram, Settings, Data sharing settings). The Standard level uses the browser pixel only, so ad blockers can stop purchase events.
The other routes are the Conversions API Gateway, which Meta describes as a no-code setup that runs on your own AWS or Google Cloud account, and a direct integration from your server to Meta's endpoint. Note which one is in place and who controls it, then audit that path.
2
Check deduplication
Confirm the pixel and the Conversions API send a matching event ID and event name, so Meta merges the browser and server versions of each event into one. Meta only deduplicates events that arrive within 48 hours of the first event with that ID. Without deduplication, purchases are double-counted and the algorithm learns from inflated numbers.
In Events Manager, look for the deduplication indicators and confirm duplicate events are being collapsed.
3
Review event match quality
Meta scores event match quality based on the customer parameters sent, such as hashed email, phone, name, and external ID. Low match quality means Meta cannot attribute events well, weakening optimization.
Check the match quality score for key events and identify which parameters are missing or malformed.
4
Audit parameter coverage
Verify that events carry the parameters Meta needs: value and currency on purchases, content IDs for catalog matching, and the customer information parameters for matching, all within consent.
Thin events without value or matching data limit both attribution and the algorithm's ability to optimize toward valuable outcomes.
5
Confirm the full event set
Check that the important events across the funnel are firing server-side: view content, add to cart, initiate checkout, and purchase. Gaps in the funnel reduce the signal Meta can learn from.
Ensure server events are not silently dropping for certain flows, such as specific payment methods.
6
Reconcile against real sales
Compare Meta-reported conversions and revenue against the source of truth. Meta tends to claim view-through and cross-device conversions, so the platform number usually overstates contribution.
Reconcile before drawing budget conclusions, and treat the source-of-truth data as the arbiter.
7
Fix and re-test
Address the gaps found: add deduplication, improve match parameters within consent, complete the event set. Then re-check match quality and deduplication after the changes take effect.
A CAPI audit is worth repeating quarterly and after any significant site or checkout change.

Common failure modes

Pixel and CAPI without a shared event ID, causing double-counting
Low event match quality from missing customer parameters
Thin events without value, currency, or content IDs
Missing funnel events, starving the algorithm of signal
Trusting Meta's reported numbers without reconciling against real sales
Leaving Shopify's data sharing on Standard, so purchases only reach Meta through the browser pixel

FAQ

Common questions

Meta does not charge for the Conversions API. On Shopify and other commerce platforms with a built-in integration, turning it on costs nothing extra. If you use the Conversions API Gateway, the only cost is the cloud hosting or partner fees, and a direct integration costs the developer time to build and maintain it.