Mail API Documentation

Self-hosted transactional email service. Send emails via a REST API from your own domain.

Quickstart

1. Register — Create an account op /register
2. Add domain — Add your domain in the dashboard
3. Configure DNS — Add the TXT verification record to your DNS
4. Verify — Click "Verify now" in the dashboard
5. Create API key — Create a key in the dashboard
6. Send — Use the API to send emails

DNS Records

After domain verification, configure these records for optimal deliverability:

DNS Provider Instructions

Cloudflare: DNS → Records → Add Record. Turn proxy (orange cloud) OFF for mail records.
Namecheap: Advanced DNS → Add New Record → TXT Record.
TransIP / Strato: DNS settings → Records → Add.

API Reference

curl -X POST https://lodata.eu/api/emails/send \
  -H "Authorization: Bearer re_xxxxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: unique-key-123" \
  -d '{
    "from": "noreply@yourdomain.com",
    "to": "customer@example.com",
    "subject": "Welcome!",
    "html": "
Hello
<p>Welcome to our service.</p>",
    "text": "Hello, welcome to our service.",
    "cc": "cc@example.com",
    "bcc": "bcc@example.com",
    "reply_to": "support@yourdomain.com"
  }'

Code Examples

Node.js

const resp = await fetch('https://lodata.eu/api/emails/send', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer re_xxxxxxxxxxxx',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    from: 'noreply@yourdomain.com',
    to: 'customer@example.com',
    subject: 'Welcome!',
    html: '<p>Hello!</p>'
  })
});
const data = await resp.json();
console.log(data.id, data.status);

Python

import requests
resp = requests.post(
    'https://lodata.eu/api/emails/send',
    headers={'Authorization': 'Bearer re_xxxxxxxxxxxx'},
    json={'from':'noreply@yourdomain.com','to':'customer@example.com','subject':'Test','html':'<p>Hello</p>'}
)
print(resp.json())

SMTP

You can also send via SMTP on port 1587 (localhost only). Authenticate with your API key as password.

Batch Send

curl -X POST https://lodata.eu/api/emails/batch \
  -H "Authorization: Bearer re_xxxxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "messages": [
      {"from":"noreply@yourdomain.com","to":"a@b.com","subject":"Mail 1","html":"
One
"},
      {"from":"noreply@yourdomain.com","to":"c@d.com","subject":"Mail 2","html":"
Twee
"}
    ]
  }'

📊 Tracking — Open & Click

Optional per email (enabled by default).

📝 Unsubscribe

Automatic for non-transactional emails. Adds List-Unsubscribe header (RFC 8058) and unsubscribe link in footer.

Use "transactional": true for password resets. Use "unsubscribe": false to disable.

📅 Calendar invites

Send calendar invites as .ics attachment:

"calendar": {
  "title": "Teamoverleg",
  "start": "2026-06-10T14:00:00Z",
  "end": "2026-06-10T15:00:00Z",
  "location": "Online",
  "attendees": [{"email": "customer@example.com"}]
}

👥 Team & Roles

Invite team members to your tenant with different roles:

📈 Reports

Error Codes