ChatGPT conversion tracking that survives ad blockers

Why one pixel is not enough

A browser pixel is the easiest thing to install and the easiest thing to lose. Ad blockers, consent banners that fire late, Safari storage limits and closed tabs all remove events before they reach OpenAI. The Conversions API closes the gap by sending the same events from your server, where nothing is blocked. The two layers only work together when each event carries one shared identifier: without it, OpenAI counts the sale twice and your oCPC bids learn from inflated numbers.

✗ pixel only: part of your conversions never reach the auction
✓ browser + server with one event_id: complete and counted once

How it works

1. The pixel is installed without touching your theme

   On Shopify, Convrail registers a web pixel through the official Web Pixel API. It runs in the sandbox Shopify provides and follows the store’s customer privacy settings. On WooCommerce, the plugin adds the snippet through wp_footer.

2. Each event is fired from the browser

   The pixel implements the OAIQ protocol natively: it captures the oppref click identifier from the landing URL, stores it in a first-party cookie for 7 days, and fires the event to OpenAI’s image endpoint with your pixel ID.

3. The same event is relayed to Convrail

   The pixel posts a compact copy of the event to Convrail with the same event_id. No personal data is included at this step.

4. Orders arrive server-side from your webhooks

   When Shopify or WooCommerce fires the paid-order webhook, Convrail builds an order_created event with the ID order_<orderId>, the exact same ID the pixel used at checkout. Emails and phone numbers are SHA-256 hashed at this moment, before anything is stored.

5. Events are batched and sent to the Conversions API

   Events are grouped per store in batches of up to 1,000, the limit of the API, and sent with a bearer token. Failed batches retry with exponential backoff; after the last attempt they land in a dead-letter queue and open a health alert instead of vanishing.

Events that are tracked

Convrail maps the standard storefront events to the OAIQ taxonomy. Amounts are converted to minor units (2599 for 25.99 EUR) as the API requires, with zero-decimal and three-decimal currencies handled correctly.

Personal data never leaves in clear text

Advanced matching improves attribution, but it must not turn into a data leak. Convrail normalizes and hashes emails and phone numbers with SHA-256 before storing or sending them, so the only user fields that reach OpenAI are emails_sha256, external_ids_sha256, IP address and user agent.

• An automated guard inspects every outgoing payload and refuses to send it if it contains an email pattern, a forbidden key such as email, phone or first_name, or a hashed field that is not a valid digest.
• The guard is covered by an automated test that tries to smuggle clear personal data through and must fail.
• Hashed values are validated as 64 lowercase hexadecimal characters; anything else is rejected before the network call.
• GDPR webhooks are honored: a customer deletion request purges their events by hashed identifier; a store uninstall purges the store.
• When the visitor has declined tracking, the event is recorded as skipped_consent and never sent.

Reliability you can audit

The Events screen in the app shows every event with its source, status and timestamp, so you can watch a browser event and its server twin arrive side by side.

Frequently asked questions