Email API

Email API for developers

One API surface for product email: transactional sending, SMTP relay, inbound webhooks, suppressions, domain authentication, delivery events, and privacy-focused aliases with EU/EEA-hosted primary service data.

Need provider-level comparison? Review Postscale as an EU transactional email provider for product teams.

Send transactional email

Trigger password resets, OTPs, magic links, receipts, confirmations, account alerts, and product notifications through REST, SDKs, or SMTP relay.

Receive email as webhooks

Point MX records at Postscale and receive parsed inbound messages, headers, bodies, attachments, and sender metadata as signed JSON webhooks.

Use SMTP where it fits

Move Rails, Django, Laravel, WordPress, PHP, and legacy systems by swapping SMTP host and credentials instead of rewriting send code.

Keep suppressions close to sending

Hard bounces, complaints, unsubscribes, and manual blocks are checked before sending so known-bad recipients do not keep damaging reputation.

Add privacy aliases

Create masked addresses for signup flows, marketplaces, feedback tools, and support workflows where users should not expose their real inbox.

Monitor deliverability

Track delivered, bounced, deferred, and complained events, import provider suppressions, review DMARC reports, and ramp new senders deliberately.

Node.js: send through the email API
await fetch("https://api.postscale.io/v1/send", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.POSTSCALE_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    from: "Acme <hello@acme.example>",
    to: ["user@example.com"],
    subject: "Confirm your account",
    html_body: "<p>Your verification code is 482193.</p>",
    text_body: "Your verification code is 482193.",
    tags: ["verification"]
  }),
});

Frequently asked questions

What is an email API?

An email API lets your application send or receive email through HTTP, SDKs, SMTP credentials, and webhooks instead of operating mail servers directly.

Can I use the API and SMTP relay together?

Yes. REST sends and SMTP-originated sends share the same verified domains, logs, suppressions, and webhook event pipeline.

Is this for marketing campaigns?

No. Postscale focuses on transactional and product email workflows: verification, password reset, receipts, account alerts, inbound replies, masked aliases, and app notifications.

What counts toward usage?

Outbound usage counts per accepted recipient, including To, Cc, and Bcc. Accepted inbound messages count toward the same monthly quota.

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