> For the complete documentation index, see [llms.txt](https://api.senderwiz.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://api.senderwiz.com/customer/reports/track-subscriber-open.md).

# Track Subscriber Open

Track when a subscriber opens a campaign email using their unique subscriber and campaign identifiers.

### 👁️ Track Subscriber Open

Use this endpoint to register an open event for a campaign by a specific subscriber.

***

#### 🔹 HTTP Request

```http
GET API-URL/campaigns/CAMPAIGN-UNIQUE-ID/track-opening/SUBSCRIBER-UNIQUE-ID
```

***

#### 🔸 URL Segments

| Segment                | Required | Description                  |
| ---------------------- | -------- | ---------------------------- |
| `CAMPAIGN-UNIQUE-ID`   | Yes      | Unique ID of the campaign.   |
| `SUBSCRIBER-UNIQUE-ID` | Yes      | Unique ID of the subscriber. |

***

#### 🔐 Authorization Header

```
X-API-KEY: your-api-key-here
```

***

#### 💻 PHP Example

```php
// Track subscriber open for campaign
$response = $endpoint->trackOpening('CAMPAIGN-UNIQUE-ID', 'SUBSCRIBER-UNIQUE-ID');

// DISPLAY RESPONSE
echo '<hr /><pre>';
print_r($response->body);
echo '</pre>';
```

***

#### 📦 Sample JSON Response

```json
{
  "status": "success",
  "data": {}
}
```