Open & Click Tracking
How tracking pixels, click redirect URLs, and ESP click-wrapping interact with PostBrix exported HTML.
Key Takeaways
- Email open tracking relies on a 1x1 transparent tracking pixel image.
- Sending platforms automatically wrap links in redirect URLs to measure click-through rates (CTR).
- Apple Mail Privacy Protection (MPP) pre-caches open pixels, inflating open rates across Apple devices.
- Ensure your links do not contain spaces or illegal characters that break ESP click-tracking wrappers.
How ESPs Track Opens and Clicks#
When you upload your PostBrix HTML into an ESP (like SendGrid or Mailchimp):
- Open Tracking: The ESP automatically injects an invisible 1x1 tracking pixel at the bottom of the body. When the recipient opens the email, the pixel loads from the ESP's server, logging an open event.
- Click Tracking: The ESP scans your HTML and replaces all
<a href="...">links with tracking redirect URLs (e.g.https://click.esp.com/c/12345?dest=https://acme.com).
Because PostBrix generates clean, standard <a> tags with explicit quotes and valid protocols, ESP click-wrapping works smoothly without breaking URLs.
Understanding Apple Mail Privacy Protection (MPP)#
Since iOS 15, Apple automatically downloads all remote email images through proxy servers before the user even opens the email:
- This records a "false open" on every email sent to an Apple Mail user.
- As a result, open rates appear inflated (often 60–80%).
- Best Practice: Rely primarily on Click-Through Rates (CTR), conversion events, and unsubscribe metrics rather than raw open rates to evaluate email performance.
Frequently Asked Questions
Does PostBrix inject its own tracking pixel into exported HTML?
No. PostBrix does not track your recipients. Tracking pixels and link redirects are inserted exclusively by your sending provider (ESP) at send time.
Why did my button link break after my ESP wrapped it?
Check if your destination URL contained unencoded spaces or curly braces that corrupted the ESP redirect engine. Ensure URLs are properly URL-encoded.