Open and click tracking

Each domain has two independent tracking toggles — open tracking and click tracking — stored on the domain and applied to mail sent from it. Both are disabled by default for every domain. Toggle them in the dashboard or with `PATCH /domains/:id` (open_tracking, click_tracking).

Open tracking

When open tracking is on, MailBlastr embeds a 1×1 transparent pixel GIF in the HTML body, with a unique reference to the email. When the recipient’s mail client downloads that image, MailBlastr records an opened event for the email — telling you exactly which message was opened.

Click tracking

When click tracking is on, MailBlastr rewrites every link in the HTML body to pass through a redirect. When a recipient clicks, the request hits MailBlastr first: it records a clicked event (with the destination URL) and then immediately redirects the recipient to the original link.

Custom tracking subdomain

By default the rewritten links and open pixel point at a MailBlastr-hosted tracking host. You can instead serve them from a custom subdomain on your own domain so tracked links stay on-brand. Set tracking_subdomain with `PATCH /domains/:id` (for example links, which produces a CNAME for links.yourdomain.com); providing it implicitly turns on custom_tracking.

• Pick a neutral label — avoid values with a negative connotation such as tracking or click.
• After setting it, publish the Tracking CNAME record MailBlastr returns and let it verify; until then the previous tracking host is used.
• A tracking subdomain can be changed but never removed — old DNS records are retained so links in already-sent email keep working.

How events surface

Open and click events appear in two places:

• In the per-email log — part of the event timeline you can view in the dashboard or fetch with `GET /emails/:id`.
• In your webhooks — opened and clicked events are delivered to your configured webhook endpoints alongside delivery, bounce, and complaint events.