How to send email from a REST API

Call Notify’s REST email API — POST /api/email/send with x-api-key, to, from, subject, and message.

Notify is a REST email API. You send transactional email by calling one HTTPS endpoint from your backend — no SMTP, no required SDK.

Canonical request: POST https://notify.cx/api/email/send
Auth: header x-api-key
Body: JSON with to, from, subject, and message (plain text or HTML)

Prerequisites

API key
Verified domain for production custom from addresses

The request

POST /api/email/send HTTP/1.1
Host: notify.cx
Content-Type: application/json
x-api-key: your_api_key

{
  "to": "user@example.com",
  "from": "noreply@your-verified-domain.com",
  "subject": "Hello from your app",
  "message": "<p>It works.</p>"
}

Successful response:

{
  "success": true,
  "data": {
    "messageId": "01000194b1dd1c04-b51e7343-6808-4a68-b2af-845feae57f8b-000000"
  }
}

Frozen rewrite alias: /api/send-email (same handler). Full field reference: API: Send Email. OpenAPI: /api-docs.

curl

curl -X POST https://notify.cx/api/email/send \
  -H "Content-Type: application/json" \
  -H "x-api-key: $NOTIFY_API_KEY" \
  -d '{
    "to": "user@example.com",
    "from": "noreply@your-verified-domain.com",
    "subject": "Hello from your app",
    "message": "<p>It works.</p>"
  }'

From your own REST API

Typical pattern: your public endpoint authenticates the user, then your server calls Notify (the API key never leaves your backend):

// Example: your POST /v1/invites handler
export async function POST(request: Request) {
  const { email } = await request.json();
  // ... authorize caller, create invite token ...

  const notifyRes = await fetch('https://notify.cx/api/email/send', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'x-api-key': process.env.NOTIFY_API_KEY!
    },
    body: JSON.stringify({
      from: 'noreply@your-verified-domain.com',
      to: email,
      subject: 'You are invited',
      message: '<p>Accept your invite in the app.</p>'
    })
  });

  if (!notifyRes.ok) {
    return Response.json(
      { error: 'email_send_failed' },
      { status: 502 }
    );
  }

  return Response.json({ ok: true });
}

Sandbox vs production

Guided dashboard test and domain verification: Sandbox vs Production
Non-delivering API rehearsal: POST /api/email/send/test (same body shape)

Related endpoints

Job	Docs
Send	api-send-email
Domains	api-domains
Webhooks	api-webhooks
Logs	api-email-logs
Usage	api-usage