> ## Documentation Index
> Fetch the complete documentation index at: https://docs.useboom.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Email open and click tracking

> Measure who opens your emails and clicks their links, with one DNS record on your sending domain.

Boom can tell you which of your emails were opened. It does this through your
email provider's tracking, which only works once your sending domain has a
**tracking subdomain** with its own DNS record. Until then, the open count on a
journey reads as not measured rather than as zero.

<Note>
  Tracking is set up once per organization, in **Settings → Email**, on the
  **Open and click tracking** card. It applies to every email Boom sends from
  your domain after it becomes active.
</Note>

## What each one measures

| | How it works | Turn it on when |
| - | - | - |
| **Opens** | A tiny invisible image is added to each email. When the recipient's mail app loads it, the email counts as opened. | You want an open rate on your email journeys. |
| **Clicks** | Every link in the email is routed through your tracking subdomain, which records the click and forwards the person to the original address. | You are ready for click reporting in Boom (coming soon). |

The two are independent: you can turn on opens, clicks, or both.

<Note>
  Open rates appear in a journey's analytics. Click counts are not shown in Boom
  yet, so turning clicks on today rewrites your links without adding a number to
  your dashboard.
</Note>

## Set it up

<Steps>
  <Step title="Choose a tracking subdomain">
    On the **Open and click tracking** card, pick a short name such as `links`.
    Boom combines it with your sending domain, so `links` on `example.com`
    becomes `links.example.com`. Use letters, numbers and hyphens only.
  </Step>

  <Step title="Turn on opens, clicks, or both">
    Flip the switches you want and press **Save**. Boom registers the subdomain
    with the email provider and shows the DNS record to add.
  </Step>

  <Step title="Add the CNAME record">
    At your DNS provider (Cloudflare, GoDaddy, Squarespace and so on), add the
    **CNAME** record exactly as shown on the card: the same name and the same
    value.
  </Step>

  <Step title="Check the record">
    DNS changes can take from a few minutes to a few hours. Press **Check
    again** on the card until the badge reads **Active**.
  </Step>
</Steps>

The badge on the card tells you where you are:

| Badge | Meaning |
| - | - |
| **Off** | No tracking subdomain yet, or both switches are off. |
| **DNS pending** | Tracking is configured, but the CNAME record isn't verified yet. Nothing is tracked until it is. |
| **Active** | The record is verified. New emails are tracked. |

<Warning>
  Once you set a tracking subdomain, you can change it later but not remove it.
  Changing it needs a new CNAME record, and tracking stays pending until that
  one is verified.
</Warning>

## Reading the numbers

Open rates are a useful signal, not an exact count:

* **Some mail apps open everything.** Apple Mail's privacy protection loads the
  tracking image for every email it receives, whether or not the person reads
  it, which pushes open rates up for Apple Mail users.
* **Some readers block images.** A person who never loads images is never
  counted as opening, even if they read the email or reply to it.

On a journey's analytics, the **Email** view tells you when its open count
can't be trusted, and shows `—` instead of a percentage in that case:

| You see | What it means |
| - | - |
| Open tracking isn't turned on | Your domain has no active tracking, so opens are not measured. |
| The tracking DNS record isn't verified yet | Tracking is configured but still pending (see the table above). |
| *N* of *M* emails were sent without tracking | Tracking is active now, but some emails in the selected period went out before it was. |

## Good to know

* **Only new emails are tracked.** Emails sent before tracking became active
  can never report opens or clicks, even after you turn it on.
* **Tracking never affects sending.** A pending or failed tracking record does
  not stop your domain from sending email.
* **Your links still work.** With clicks on, the link a person sees in the email
  points at your tracking subdomain first, then forwards to the original
  address, unsubscribe links included.


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