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

# POST Start Campaign

> Start or schedule a campaign for execution.

## Start campaign

`POST /api/campaigns/:id/start`

Start sending a draft or scheduled campaign immediately.

### Headers

**Cookie** `string` *required*

Session cookie (login via POST /api/auth/login)

### Path parameters

**id** `integer` *required*

Campaign ID.

```bash cURL theme={null}
curl -X POST https://zeplo.ai/api/campaigns/1/start \
  -H "Cookie: connect.sid=s%3A7HImZ-T2BxWSbUsf9dtWdOlBW4rVuORO.5J0Do0NyvBu%2BkTvu1aHvtNs00BKhkpUKTwiokLS0cpw"
```

```json Response theme={null}
{
  "success": true,
  "message": "Campaign started successfully",
  "data": {
    "id": 1,
    "status": "running",
    "startedAt": "2026-01-15T14:00:00Z"
  }
}
```

***

## Send campaign via API key

`POST /api/campaigns/send/:apiKey`

Trigger a campaign using an API key (for external integrations).

### Path parameters

**apiKey** `string` *required*

API key in URL path.

### Body parameters

**campaignId** `integer`

Campaign ID to send.

**contactIds** `integer[]`

Specific contact IDs to send to.

**scheduledAt** `string`

ISO 8601 datetime for scheduled send.

```bash cURL theme={null}
curl -X POST https://zeplo.ai/api/campaigns/send/zeplo_ak_abc123 \
  -H "Content-Type: application/json" \
  -d '{ "campaignId": 1 }'
```


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.