> ## Documentation Index
> Fetch the complete documentation index at: https://leadtrackr.io/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# Create Server-Side Lead
> Create a lead from your backend with API key authentication.
This endpoint is designed for **server-side** integrations. It requires an API key sent via the `X-API-Key` header.
If a lead with the same `uniqueEventId` already exists, it will be updated instead of duplicated.
## Request body
The public ID of the project to create the lead in. You can find this in the [LeadTrackr Dashboard](https://app.leadtrackr.io) under **Settings**.
Contact information for the lead.
First name
Last name
Email address
Phone number (including country code, e.g. `+31612345678`)
Company name
Attribution and tracking data. At least one of `userData` or `attributionData` must contain data.
Google Click ID
Google Web-to-App Broad ID
Google Analytics Client ID (e.g. `1234567890.1234567890`)
Google Analytics Session ID
Facebook Browser ID (`_fbp` cookie value)
Facebook Click ID (`_fbc` cookie value)
Form submission data. You can include any additional custom fields — they are stored as-is.
Name of the form (e.g. `"Contact Form"`, `"Quote Request"`)
Message or description submitted with the form
Unique identifier to deduplicate submissions. If a lead with the same `uniqueEventId` already exists in the project, the existing lead is updated instead of creating a duplicate.
Any additional fields you include (e.g. `formCustomField1`, `campaign`, `source`) are passed through and stored as-is.
Device and browser information. Used to improve attribution accuracy for GA4 and Meta integrations.
IP address of the user
Browser user agent string
Channel flow tracking value (UTM journey). Also accepted as `lt_channelflow`.
A user-provided identifier to link this lead to your own system (e.g. your CRM lead ID or form submission ID). Max 255 characters. Also accepted as `unique_identifier`.
## Response
A description of the result. Either `"Lead created successfully"` or `"Lead updated successfully"`.
The ID of the created or updated lead.
The unique identifier for the lead, or `null` if not provided.
```bash cURL theme={null}
curl -X POST https://app.leadtrackr.io/api/leads/createServerSideLead \
-H "Content-Type: application/json" \
-H "X-API-Key: your-api-key-here" \
-d '{
"projectId": "your-project-id",
"userData": {
"firstName": "Jane",
"lastName": "Smith",
"email": "jane@example.com",
"phone": "+31687654321",
"companyName": "Acme Inc."
},
"attributionData": {
"gclid": "xyz789",
"cid": "9876543210.9876543210",
"fbp": "fb.1.1612345678.9876543210"
},
"formData": {
"formName": "Contact Form",
"formMessage": "Interested in your services",
"uniqueEventId": "evt_xyz789"
},
"deviceData": {
"ipAddress": "203.0.113.50",
"userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7)"
},
"uniqueIdentifier": "crm-lead-789"
}'
```
```javascript JavaScript theme={null}
const response = await fetch("https://app.leadtrackr.io/api/leads/createServerSideLead", {
method: "POST",
headers: {
"Content-Type": "application/json",
"X-API-Key": "your-api-key-here"
},
body: JSON.stringify({
projectId: "your-project-id",
userData: {
firstName: "Jane",
lastName: "Smith",
email: "jane@example.com",
phone: "+31687654321",
companyName: "Acme Inc."
},
attributionData: {
gclid: "xyz789",
cid: "9876543210.9876543210"
},
formData: {
formName: "Contact Form",
uniqueEventId: "evt_xyz789"
},
uniqueIdentifier: "crm-lead-789"
})
});
const data = await response.json();
console.log(data);
```
```php PHP theme={null}
$ch = curl_init("https://app.leadtrackr.io/api/leads/createServerSideLead");
curl_setopt_array($ch, [
CURLOPT_RETURNTRANSFER => true,
CURLOPT_POST => true,
CURLOPT_HTTPHEADER => [
"Content-Type: application/json",
"X-API-Key: your-api-key-here"
],
CURLOPT_POSTFIELDS => json_encode([
"projectId" => "your-project-id",
"userData" => [
"firstName" => "Jane",
"lastName" => "Smith",
"email" => "jane@example.com",
"phone" => "+31687654321",
"companyName" => "Acme Inc."
],
"attributionData" => [
"gclid" => "xyz789",
"cid" => "9876543210.9876543210"
],
"formData" => [
"formName" => "Contact Form",
"uniqueEventId" => "evt_xyz789"
],
"uniqueIdentifier" => "crm-lead-789"
])
]);
$response = curl_exec($ch);
curl_close($ch);
$data = json_decode($response, true);
print_r($data);
```
```json 201 theme={null}
{
"message": "Lead created successfully",
"leadId": 43,
"uniqueIdentifier": "crm-lead-789"
}
```