OpenMail is a Developer tools tool: Email inboxes for AI agents, with replies pushed by webhook.

How much does OpenMail cost?

OpenMail uses a Freemium model; see the vendor's pricing page for current plans.

What are the best alternatives to OpenMail?

Community-listed alternatives to OpenMail include MachineMail, agentmash, Pairon, Whereby.

What does OpenMail integrate with?

OpenMail integrates with OpenClaw, Hermes Agent, Claude Code, ChatGPT, LangChain, n8n and more.

OpenMail

Email inboxes for AI agents, with replies pushed by webhook

FreemiumTeam communication Developer tools

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OpenMail is a developer tools tool for Developers and Small businesses, offered as freemium. Popular alternatives include MachineMail, agentmash, Pairon.

About OpenMail

OpenMail is an email API built for AI agents, run by UAB All Systems Operational in Vilnius, Lithuania, and co-founded by Jokūbas Vaičiulis and Armandas Vaičikauskas. Each agent gets its own address with a separate sending reputation, so it can sign up for services, receive one-time codes, answer customers and keep a real conversation going instead of only sending one-way mail.

Inboxes are created with one API call or the CLI, and inbound mail reaches the agent over a webhook or WebSocket, so nothing has to poll. Threading, allow and block rules per address or domain, and a suppression list come on every plan, and PDFs, CSVs and images can be parsed into plain text at extra cost or with your own provider key. Plugins for OpenClaw and Hermes offer tool, notify and channel modes, and it is in the ChatGPT plugin directory. Free gives 3 inboxes and 3,000 emails a month on openmail.sh addresses; Pro is €9 a month with 10 inboxes, 10,000 emails and custom domains, then usage-based overage.

It fits developers who need agents to both send and receive. MachineMail covers similar agent inboxes with coding-agent tooling, while Resend is a stronger pick for outbound product email but is not built around inbound threads. The pricing page mixes dollar and euro figures, and very large senders need Enterprise for dedicated IPs.

OpenMail launched on Product Hunt on November 4, 2026 and was ranked #5 on Product Hunt's daily leaderboard for that date. Buying tip: set the Pro spending limit, because overage bills at the end of the cycle rather than blocking agents.

Key features of OpenMail

One API call or CLI command creates a dedicated agent inbox
Inbound mail delivered in real time over webhook or WebSocket
Full email threading so agents reply in the same conversation
PDF, CSV and image attachments parsed into plain text (extra cost)
Allow and block rules per address or domain
Custom domains with DKIM, SPF and DMARC on Pro
OpenClaw and Hermes plugins with tool, notify and channel modes
Hosted in the EU with GDPR coverage on every plan

Pros and cons

Pros

Built for receiving and replying, not only sending
Each inbox has its own sending reputation
Free plan needs no credit card
No per-seat pricing, with unlimited members
EU hosting suits teams with data residency needs

Cons

Pricing page mixes $9 and €9; overage rates are in euros
Free plan caps sending at 100 emails a day
Free plan appends a "Sent with OpenMail" footer
Dedicated sending IPs only on Enterprise
Young product with a small public track record

OpenMail pricing

OpenMail uses a freemium model.

Plan	Price	Includes
Free	€0 / mo	3 inboxes, 3,000 emails/mo (100/day), 3 GB, openmail.sh addresses
Pro	€9 / mo	10 inboxes, 10,000 emails, custom domains; then usage-based
Enterprise	Custom	Dedicated sending IPs, SSO, 1-hour SLA, custom DPA

Source: openmail.sh · checked on Nov 5, 2026

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How OpenMail compares in Developer tools

Rank by votes: #2 / 93
Starting price: $0
Free alternatives: 23

OpenMail ranks #2 of 93 developer tools tools by community votes and is not directly comparable on price.

Common use cases

1Browser agents that finish signups with emailed verification codes
2Support agents that triage and answer customer mail in-thread
3Forwarding invoices to an agent inbox and getting structured data back
4Giving ChatGPT or Claude Code an inbox of its own
5Running many tenant inboxes from one account for an agent product

Best for

Developers building AI agents that need their own email address to receive, thread and answer mail.

Not ideal for

Teams that mainly send marketing or transactional email at high volume (Resend, MachineMail).

Integrations

OpenClaw
Hermes Agent
Claude Code
ChatGPT
LangChain
n8n
Vercel AI SDK

Our take

OpenMail is a well-scoped choice when an agent has to hold real email conversations, and the free plan is enough to prove the flow. Move to Pro once you need custom domains, and cap spending before you let agents run unattended.

FAQ

What is OpenMail?: OpenMail is a Developer tools tool: Email inboxes for AI agents, with replies pushed by webhook.
How much does OpenMail cost?: OpenMail uses a Freemium model; see the vendor's pricing page for current plans.
What are the best alternatives to OpenMail?: Community-listed alternatives to OpenMail include MachineMail, agentmash, Pairon, Whereby.
What does OpenMail integrate with?: OpenMail integrates with OpenClaw, Hermes Agent, Claude Code, ChatGPT, LangChain, n8n and more.
Which platforms does OpenMail support?: OpenMail is available on web.
Who is OpenMail for?: Developers building AI agents that need their own email address to receive, thread and answer mail.

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