Email for developers

Email infrastructure for every product you ship

Receive email as a webhook. Send with one API. Manage unlimited domains. Built for multi-product SaaS teams and the AI agents they build.

What you get

Everything you need to ship with email

How it works

Three steps to start

  1. 1

    Sign up and get an API key

    Instant API key — no waiting, no approval. Start building in under 5 minutes.

  2. 2

    Add your first domain

    Point MX records at MailKite. We verify DNS and activate the domain automatically.

  3. 3

    Receive or send your first email

    Register a webhook for inbound, or fire the send API for outbound. Clean JSON in, clean API out.

Built for

Developers who ship fast

Multi-product builders

Ship 10+ domains without rebuilding email plumbing per product. One platform, one API key, unlimited domains.

Developers adding email features

Reply-by-email, support inboxes, inbound parsing, verification codes — clean JSON webhooks, not a wiring project.

AI agent builders

Agents with their own inbox, two-way threads, and MCP integration. Human supervision built in.

Questions

What is MailKite?

MailKite is an inbound-first email platform for developers. Receive email as a webhook, send with one API, manage unlimited domains. Built for teams shipping multiple products and the AI agents they build.

How is this different from SendGrid or Postmark?

SendGrid and Postmark are send-first platforms with inbound bolted on. MailKite is inbound-first: every incoming email becomes a clean JSON webhook. We also include unlimited free domains, graceful overage, and MCP-native agent support.

Is there a free tier?

Yes. MailKite is free on unlimited domains. No credit card required. You pay only when you need higher volume or premium features.

What languages do you support?

Official SDKs for Node.js, Python, Go, Ruby, PHP, Java, .NET, and Rust. Plus an MCP server for AI agents and an SMTP relay for legacy apps.

Start shipping email today

Unlimited domains, free. No credit card required.