Reliable email delivery,built for developersand teams

Send transactional and broadcast email across unlimited domains — with an API, SMTP relay, and deliverability tooling on the edge.

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Transactional Email

Fire password resets, receipts, and alerts through a single fast API.

Broadcasts

Design and send newsletters and campaigns to your whole audience.

Deliverability

SPF, DKIM, DMARC, and suppression lists keep you out of the spam folder.

Everything you need to send email

One platform for transactional email, broadcasts, and the infrastructure that gets them delivered.

Developer API
Send in one call
REST API & SMTP relay
Official SDKs & examples
Idempotent, typed responses
Multi-Domain
Unlimited domains
Verify domains in minutes
Per-domain sending identities
One console for every brand
Analytics
Real-time insight
Opens, clicks & bounces
Delivery & complaint tracking
Webhooks for every event
Edge Infrastructure
Fast & reliable
Built on Cloudflare Workers
Low-latency global sending
Scales from 1 to millions

Your first email in minutes

A single HTTP request is all it takes. Authenticate your domain, grab an API key, and send.

send-email.ts
await fetch("https://api.markrelay.com/v1/emails", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${MARKRELAY_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    from: "MarkRelay <hello@yourdomain.com>",
    to: "user@example.com",
    subject: "Welcome aboard 🎉",
    html: "<p>Thanks for signing up!</p>",
  }),
});

Prefer SMTP? Point your existing mailer at our relay and keep your current code.

Who Is It For?

Anyone who needs email that just works

🧑‍💻

Developers

Drop email into any app with a clean API, SMTP relay, and webhooks — no infrastructure to babysit.

🚀

Product Teams

Ship reliable transactional email — verifications, receipts, and notifications that always arrive.

📣

Marketers

Build, send, and measure broadcasts to your whole audience from one simple console.

🏢

Agencies

Manage sending for unlimited client domains, each with its own identity and analytics.

🤖

AI Agents

Give automated workflows a programmable mailbox to send and react to email events.

💡

Startups

Start free, then scale to millions of emails on transparent, pay-as-you-grow pricing.

Ready to ship email that lands?

Join MarkRelay today and send your first email in minutes.

Why choose MarkRelay?

The deliverability of a dedicated platform, the simplicity of a single API.

Email APISMTP RelayBroadcastsWebhooksSPF / DKIM / DMARCSuppression ListsReal-time AnalyticsEdge Delivery