Free Developer Utility

Meta CAPI & Pixel Deduplication Generator

Eliminate duplicate conversions and missing event IDs in Meta Events Manager. Generate synchronized client-side fbq calls and server-side CAPI payloads in seconds.

⚙️ Event Configuration

Processed locally in memory via Web Crypto API. Never sent to any server.

⚠️ Deduplication Golden Rule:

Both browser pixel and server CAPI must pass the exact same event_id string within a 48-hour window. Character casing must match identically.

1. Client-Side Browser Pixel Payload
2. Server-Side CAPI JSON Payload (Graph API)

Need to verify if your live pixel is deduplicating?

Checkout Detective monitors both browser and CAPI signals live in the Chrome side panel.

Verify Live Pixel Free →
Developer Workflow

How to Use This CAPI Generator

Generate clean, duplicate-proof Meta telemetry in 3 quick steps.

1

Select Event & Architecture

Pick your conversion action (e.g. Purchase) and choose whether your code runs in Shopify Customer Events (Web Pixels), standard Liquid, or headless.

2

Preview Synchronized Code

Observe how the generated client-side fbq call and server CAPI JSON share the identical event_id string.

3

1-Click Copy & Deploy

Copy the snippets into your Shopify Web Pixel or backend webhook handler (Cloudflare Worker, AWS Lambda, or Node server).

Meta Events Manager Specifications

What to Expect & How Meta Deduplicates

🔑 The Exact Event ID Match Rule

Meta looks at two signals to deduplicate: event name (e.g. Purchase) and event ID. If both the browser pixel and server CAPI transmit event_id: "shopify_purchase_5849201948" within a 48-hour window, Meta keeps the richer event and discards the other as duplicate.

🔒 SHA-256 Hashing for Event Match Quality

Never transmit customer emails or phone numbers in plaintext over CAPI. Always strip leading/trailing spaces, lowercase the string, and hash with SHA-256. This lifts your Meta Event Match Quality (EMQ) from 4.0 to 8.5+.

Want the complete engineering teardown?

Read our 1,780-word guide on debugging Meta CAPI deduplication in the Shopify Customer Events sandbox.

Read Engineering Guide →
Verify Live Pixel Telemetry

Verify if your live store is double-firing purchase events.

Checkout Detective's Chrome DevTools side panel intercepts browser fbq calls and backend network beacons in real time — warning you immediately if deduplication event_id is missing.

5 Free Audits / Month
Zero-PII Local In-Browser Processing
Shopify & Plus Verified
Manifest V3 Extension

Compatible with Google Chrome, Brave, Microsoft Edge, and Opera. No credit card required.