Home / Mektup vs AgentMail
ComparisonNeed one mailbox a human and an agent both check, or hundreds of mailboxes for a fleet of agents - Mektup does both, on your own domain. Every mailbox gets a real IMAP/SMTP/webmail inbox plus the same REST API and MCP server AgentMail offers, and receiving mail never counts against your quota.
AgentMail is API-first, agent-first infrastructure: it lets you spin up inboxes programmatically as a data primitive for a multi-agent framework like CrewAI or LangChain, with MCP tooling built around threading and drafting. What it isn't built for is a human sitting down and reading mail like a normal inbox - there's no webmail interface, and the free tier doesn't include a custom domain at all (agents get an address on AgentMail's own domain, not yours).
Mektup starts from the opposite direction: a real mailbox on a domain you own, with IMAP/SMTP for Outlook/Apple Mail/your phone and a webmail dashboard - that also exposes every operation as a REST API and a native MCP server. There's no limit on how many mailboxes you create, so the same account that gives one person a normal inbox can also spin up a mailbox per agent, per workflow, or per customer - hundreds of them if you need it. Receiving doesn't count against your plan's email quota at all; only outbound sending is metered, so a fleet of mostly-receiving agent inboxes barely touches the free tier. Each mailbox can also fire a signed webhook the instant new mail lands, so an agent reacts immediately instead of polling for it.
| Mektup | AgentMail | |
|---|---|---|
| Custom domain on free tier | Yes | No |
| Webmail dashboard for humans | Yes | No - API/MCP only |
| IMAP/SMTP (Outlook, Apple Mail, phone) | Yes | Supported as a secondary/dev feature |
| REST API | Yes | Yes |
| MCP server for AI agents | Yes, native | Yes, native |
| Webhook on new mail | Yes, HMAC-signed | Yes |
| Built-in website contact forms | Yes | No - build your own, wired to a webhook |
| Team member logins | Pro: 5 included | No - headless, no dashboard concept of "team" |
| Best for | One inbox for a human, or hundreds for a fleet of agents - your call | Bot-only inboxes, no option for a human interface |
| Mailboxes per account | Unlimited | 3 on the free tier |
| Free tier | 1 domain, 3,000 emails/mo, 3GB, no daily cap | 3 inboxes, 3,000 emails/mo, 3GB, no custom domain, 100/day cap |
| Volume | Mektup | AgentMail |
|---|---|---|
| 100 emails/mo | Free | Free |
| 300 emails in one day, bursty (typical agent usage) | Free - no daily cap, only a 3,000/mo ceiling | Requires a paid plan - free tier caps at 100/day |
| 5,000 emails/mo | $20/mo (Starter, includes a real mailbox) | $20/mo (Developer - free caps at 3,000/mo) |
| 50,000 emails/mo | $20/mo (Starter, 10 domains + a real mailbox) | $200/mo (Startup plan, 150,000/mo cap - no tier between $20 and $200 covers 50k) |
AgentMail pricing per public third-party reporting as of this page's last update - verify current numbers at agentmail.to/pricing before budgeting off this table.
There's no cap on how many mailboxes an account can create - one domain can host a mailbox per agent, per customer, or per automated workflow, all reachable through the same REST API and MCP server. Receiving mail doesn't count against your plan's email quota at all; only outbound sending is metered, so a fleet of agents that mostly reads and occasionally replies barely touches the free tier's 3,000/mo sending allowance. AgentMail is built only for that pattern. Mektup does it too, and also gives you the option nobody else on this page does: the same mailbox works as a normal inbox for a person, whenever you need one to.
Mektup is an AgentMail alternative for teams that want the agent-first capabilities and a human-usable inbox: the same REST API, native MCP server, and instant webhooks - on real mailboxes a person can open in Outlook, Apple Mail, or webmail, with team logins. If your model is "an agent runs the inbox, but people can read, join, and take over any thread," that's the case Mektup is built for - see the shared inbox for humans and AI agents guide. And if you're provisioning inboxes per customer rather than per agent, see multi-tenant email.
hello@yourdomain.com.Yes. AgentMail treats an inbox as a disposable API object for a bot - there's no webmail, and the free tier doesn't include a custom domain at all. Mektup gives you a real mailbox on your own domain - one a human can check in Outlook, and an agent can drive over the same REST API/MCP server AgentMail offers - and there's no limit on how many mailboxes you create, so it covers AgentMail's bulk-inbox use case too.
Yes. Mektup's REST API and native MCP server let an agent register a domain, create a mailbox, send mail, and read replies and threads entirely on its own - the same tool set AgentMail's MCP server offers, just on infrastructure that also gives a human a real inbox to check.
At the free tier, Mektup includes a custom domain and 3,000 emails/month with no daily cap; AgentMail's free tier is also 3,000 emails/month across 3 inboxes, but throttled to 100/day and with no custom domain at all. At the first paid tier, both are $20/month, but Mektup's $20 (Starter) covers 50,000 emails and 10 domains, versus AgentMail's Developer plan at 10,000 emails.
Yes. There's no limit on mailbox count per account, and receiving mail doesn't count against your plan's email quota - only outbound sending is metered. A domain with hundreds of mostly-receiving agent inboxes fits comfortably on the free tier's sending allowance.
It can get notified. Every mailbox can have a webhook configured that fires an HMAC-signed POST the instant new mail arrives, with the sender, subject, and body already in the payload - no need to poll list_messages to find out something new landed.
Mektup - the same agent-first capabilities (REST API, native MCP server, webhooks, unlimited programmatic inboxes) on real mailboxes a person can also open over IMAP/SMTP or in a full webmail dashboard, with team logins. One inbox, operated by both the agent and the humans. See the shared inbox guide.