Domains

Open and click tracking

Per-domain open and click tracking: how the open pixel and link rewriting work, and how events surface.

Each domain has two independent tracking toggles — open tracking and click tracking — stored on the domain and applied to mail sent from it. API-created domains default to open tracking off and click tracking on; the dashboard asks for both explicitly. Toggle either setting 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. A request for that image records an opened event. This identifies the tracked message, but does not prove that a person read it: image proxies and privacy tools may request the pixel automatically.

Click tracking

When click tracking is on, MailBlastr rewrites eligible HTTP and HTTPS links through a redirect. A request to that redirect records a clicked event with the destination URL, then continues to the original destination. Non-web links such as mailto:, unsubscribe and preference links, and links already wrapped by the tracker are excluded. Automated link scanners can also generate requests.

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.

Choose an unused subdomain, such as links, and confirm that it does not conflict with an existing website or DNS record.
After setting it, publish the Tracking CNAME record MailBlastr returns and let it verify; until then links use MailBlastr's shared tracking host.
You can change the subdomain or switch off custom_tracking for new messages. MailBlastr retains previous tracking host bindings and record entries for already-sent links; keep the corresponding DNS records in your DNS provider while those links need to work. Deleting the sending domain is a separate action.

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.

Engagement tracking is approximate. Image-proxying and privacy features can inflate opens, blocked images can undercount them, and link scanners can inflate clicks. Use these events as directional signals alongside meaningful activity in your application.