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Transactional emailSend the verification codes, password resets, receipts, and notifications your product runs on - from your own domain, with one API call. It's the transactional email API you'd reach for anyway. The difference: the address you send from is a real mailbox, so the replies, questions, and bounces land somewhere you can read, instead of vanishing into a webhook.
// send a verification code from your backend await fetch("https://api.usemektup.com/v1/emails", { method: "POST", headers: { Authorization: `Bearer ${process.env.MEKTUP_API_KEY}`, "Content-Type": "application/json", }, body: JSON.stringify({ from: "noreply@yourapp.com", to: "new-user@example.com", subject: "Your verification code", html: "<p>Your code is <b>418205</b></p>", text: "Your code is 418205", }), });
Plain HTTPS, no SDK to install, works from any backend, serverless function, or edge runtime. Send styled html and a text fallback in the same request.
Most transactional email providers are one-directional - they fire the message and stop. But customers reply to receipts, answer notifications, and respond to offers, and with a send-only API those replies bounce or disappear. Because Mektup runs a real inbox behind every address, a reply to noreply@yourapp.com (or better, hello@yourapp.com) lands in an actual mailbox you can read in the dashboard, over IMAP, or through the API - and an AI agent can even act on it.
Every domain gets a real DKIM keypair, plus the exact SPF and DMARC records to add, so your transactional mail is properly authenticated. Mektup runs its own outbound mail servers and talks directly to the recipient - so delivery status (sent / deferred / bounced) comes from the receiving server's real SMTP response, not a guess or a tracking pixel. When Gmail defers something, you see Gmail's actual reason.
Every send is a documented REST endpoint and a native MCP tool, so an AI coding agent can wire up (and trigger) transactional email itself, and a human can watch the whole stream in Mektup's webmail. Same platform, both audiences.
The free tier includes a full domain, 3,000 emails a month, 300 a day, and one mailbox - no credit card. Register your domain, add the DNS records it hands you, and your first transactional send is minutes away.
Getting started is free - 3,000 emails a month, 300 a day, one mailbox, no credit card. Paid plans scale to 50,000 and 150,000 emails a month. See the full pricing.
Yes. A single authenticated POST to /v1/emails sends a verification code, password reset, receipt, or notification from your own domain, with real DKIM/SPF/DMARC. It does everything a sending-only transactional API does - and because Mektup also runs real inboxes, replies land in a mailbox instead of a webhook void.
Yes. The send endpoint accepts an html field alongside text, so you send fully styled HTML - receipts, branded welcome mail, notifications - with a plain-text fallback in the same request.
Replies arrive in the real mailbox behind your sending address - readable in the webmail, over IMAP, or through the API. Delivery outcomes come from Mektup's own outbound server's real SMTP response, so you see exactly why something didn't land.
No. Mektup is fully managed and hosts all the infrastructure. Add a few DNS records for your domain once, then just call the API - nothing to install, patch, or keep online.