Open and click tracking

Turn it on when sending

Add tracking_options to send an email or create a draft:

curl -X POST "$EE_URL/api/v1/emails" \
  -H "X-API-KEY: $EE_KEY" -H "Content-Type: application/json" \
  -d '{
    "account_id": "acc_ba1fa6938d8548298e8ce62e4b4b4e99",
    "to": ["ana@example.com"],
    "subject": "Our offer",
    "body": "<p>See <a href=\"https://acme.com/offer\">the offer</a>.</p>",
    "tracking_options": { "opens": true, "links": true, "label": "campaign-7" }
  }'

boolean

Add an invisible 1×1 image that records opens.

boolean

Send every http(s) link through the engine, which records the click and redirects.

string

Your own tag, sent back in the events.

string

A domain of yours that points at the engine (a CNAME), such as links.acme.com. It’s used in the tracking URLs instead of the engine’s address, so links look like your own.

Response 201

{ "object": "EmailSent", "account_id": "acc_ba1fa6938d8548298e8ce62e4b4b4e99", "message_id": "84c3db9476d84b288bc6fa055a576764@mail-api.example.com", "provider_id": null, "tracking_id": "trk_5d0c3e2f1a4b4c6d8e7f9a0b1c2d3e4f" }

The response contains a tracking_id. The sent email has the same tracking_id once it syncs. Tracking works on the HTML body only, so plain-text emails can’t be tracked.

Events

Subscribe a webhook endpoint to tracking.open and tracking.click.

tracking.open

{
  "object": "Event",
  "id": "evt_9e8d7c6b5a4f43e2d1c0b9a8f7e6d5c4",
  "type": "tracking.open",
  "created_at": "2026-10-06T10:01:44Z",
  "account_id": "acc_ba1fa6938d8548298e8ce62e4b4b4e99",
  "endpoint_id": "we_e3f1a2b4c5d64e7f8a9b0c1d2e3f4a5b",
  "data": {
    "tracking_id": "trk_5d0c3e2f1a4b4c6d8e7f9a0b1c2d3e4f",
    "label": "campaign-7",
    "message_id": "84c3db9476d84b288bc6fa055a576764@mail-api.example.com",
    "email_id": "email_94a0d77db739407e932c3b97fef44aac",
    "date": "2026-10-06T10:01:44Z",
    "ip": "203.0.113.7",
    "user_agent": "Mozilla/5.0 …"
  }
}

tracking.click has the same fields plus url, the link that was clicked. email_id is the sent email’s copy in the Sent folder, or null if it hasn’t synced yet.

Good to know

Opens are a hint, not proof. Some mail apps block images, so opens are missed. Others, such as Apple Mail Privacy Protection and Gmail’s image proxy, load images on their own, so an email can look opened when nobody read it. Clicks are more reliable.
Tracked links are signed, so nobody can use your engine to redirect to other sites.

Getting started

Accounts

Emails

Webhooks

Reference

Open and click tracking

Turn it on when sending

Events

Good to know

​Turn it on when sending

​Events

​Good to know

Turn it on when sending

Events

Good to know