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Send with your stack

Send emails over raw HTTP / cURL

The canonical POST /emails request — headers, body, and response — that any HTTP client can reproduce.

At its core, MailBlastr is a plain JSON REST API — every SDK and framework guide is a wrapper around the same HTTP request shown here. If your language or tool can make an HTTPS POST with a couple of headers and a JSON body, it can send email through MailBlastr. Node.js / TypeScript users can skip the raw HTTP call and npm install mailblastr instead.

This is the canonical request. Reproduce it in curl, Postman, an HTTP client library, or a no-code tool.

Prerequisites

  1. A verified domain so your from address is allowed. (guide)
  2. An API key (mb_...) for the Authorization header. (Authentication)
POST/emails

Request headers

Authorizationstringrequired

Your API key as a Bearer token: Bearer mb_xxxxxxxxx. See Authentication.

Content-Typestringrequired

Must be application/json — the body is a JSON object.

Idempotency-Keystringoptional

Optional. A unique key so a retried request sends only once. See Idempotency keys.

The canonical request

Replace mb_xxxxxxxxx with your key and use a from address on your verified domain. The minimum body is from, to, subject, and one of html / text.

curl -X POST 'https://www.mailblastr.com/api/emails' \
  -H 'Authorization: Bearer mb_xxxxxxxxx' \
  -H 'Content-Type: application/json' \
  -d '{
    "from": "Acme <hello@yourdomain.com>",
    "to": ["delivered@example.com"],
    "subject": "Hello from MailBlastr",
    "html": "<p>Sent over raw HTTP.</p>"
  }'
Any HTTP client works — curl, wget, HTTPie, Postman, Insomnia, or your language's native client. The full set of body fields (cc, bcc, reply_to, headers, attachments, tags, scheduled_at) is documented in the Send Email API reference.

Handling the response

A successful send returns HTTP 200 with the new email id:

{
  "id": "49a3999c-0ce1-4ea6-ab68-afcd6dc2e794"
}

On failure the status is non-2xx and the body is a { statusCode, name, message } error object. Always branch on the HTTP status before reading the id.

{
  "statusCode": 422,
  "name": "validation_error",
  "message": "The domain yourdomain.com is not verified."
}
Send this request only from a server (or a private script). The mb_ API key authenticates as your account — never put it in a browser, a mobile app, or any client a user can inspect. Load it from an environment variable, not a literal in your code.

Next steps