Communication is the heart of your organization. Own it.
Every contract, every customer conversation and every internal decision passes through email. RapidMX puts that back under your control without asking anyone to give up the tools they're used to.
Nobody else reads your mail
Your data lives on hardware you own, in the country you choose. There's no ad profile, no AI training on your inbox and no provider with a master key. Administrators manage the platform, not everyone's mail.
Stop paying rent per person
Cloud suites charge every user, every month, forever, and raise prices without notice. RapidMX is free open-source software. You pay for the server it runs on, whether that is ten people or ten thousand.
No lock-in, in or out
Bring your data with you by importing mbox and Outlook PST files, and take it with you any time as mbox or JSON. Your team keeps using the same apps they already know.
One platform for how your team communicates
Mail, calendar, contacts and tasks are core built-in features. Video meetings, booking pages, CRM and more are shipped as plugins so that you only use what your team needs.
Webmail people enjoy
Conversations, a Focused and Other inbox, labels, rich compose with autocomplete, scheduled send and recall, read receipts, signatures, rules and automatic replies.
Learn moreCalendar and scheduling
Recurring events, meeting invitations and responses, and room and equipment mailboxes that accept bookings on their own.
Learn moreContacts and tasks
Contacts with contact lists, vCard import and export, and a task list that lives right next to your mail.
Learn moreVideo meetings
Host video calls from your own personal meeting URL or add a private call via calendar invite or shared link, relayed through your own TURN server so that calls remain private and work even through strict firewalls.
Learn moreBooking pages
Public scheduling pages that check your real availability, confirm by email and let guests reschedule or cancel on their own.
Learn moreCRM and campaigns
Contacts, companies, sales pipelines, mailing lists, campaigns and automations, connected to the mailboxes your team already works in.
Learn moreTeam chatComing soon
Teams, channels and threads for the quick back-and-forth that does not belong in an inbox.
Learn moreThe apps you already use
Supports existing mail apps via Exchange ActiveSync. Autodiscover makes setup simple with just an email address and password.
Learn morePrivate by design, not by policy
A privacy policy is a promise. Encryption and self-hosting are guarantees. RapidMX is the first open-source communications platform with turn-key federated S/MIME encryption — including automated X.509 certificate issuance, key discovery and rotation — that works with standard mail clients.
End-to-end encryption, built in
S/MIME signing and encryption happen in the browser, and every person gets their own keys, kept in a vault only they can unlock. Make encryption automatic, optional or off for each kind of recipient.
Modern sign-in
Passkeys and security keys, authenticator apps, one-time codes and recovery codes. App passwords keep existing mail apps working, even when two-step sign-in is turned on.
Spam and malware, fail-closed
Every message is scored by rspamd and scanned by ClamAV. If a scanner is down, mail is held in quarantine or sent to Junk, never waved through to the inbox. Your users reports teach the filter.
Trusted delivery
DKIM signing and verification, SPF and DMARC with a live DNS checklist per domain, and mandatory TLS between mail servers.
eDiscovery, scoped to the matter
Open a matter to place its custodians under legal hold, then search and export their mail, contacts and calendars across the matter’s date range. Every search, export and download is audited.
Recovery with dual control
Organizations that must be able to recover encrypted mail can enable key escrow: every request needs M-of-N approvals and lands in a tamper-evident, hash-chained audit log.
Everything an IT team needs, in one console
A guided setup wizard takes you from a fresh install to your first working mailbox. After that, one admin console covers the whole organization. Add a domain and it works within seconds, with nothing to restart.
- Host as many mail domains as you like, each with a live DNS checklist for MX, SPF, DKIM and DMARC
- Mailboxes, aliases, nested distribution lists, shared mailboxes with delegation, and bookable rooms
- Transport rules, retention policies, legal hold and eDiscovery search and export
- Data-subject export and erasure requests for GDPR and similar laws
- A quarantine queue and a complete audit log
- Customize with your own logo, name, colours, header and footer
- Plugins you search, install, upgrade and remove from the console
Get up and running in an hour
A rented virtual server, the rack in your office or your existing cluster: pick a path and you'll be signing in to your own mail server today. Choose between MongoDB or PostgreSQL, disk or S3 storage, Postfix or Amazon SES.
A single script installs a lightweight Kubernetes (k3s), HTTPS certificates from Let's Encrypt, Postfix and RapidMX on a Debian, Ubuntu or RHEL server.
curl -fsSLO https://raw.githubusercontent.com/rapidmx/server/main/single_node_install.sh
chmod +x single_node_install.sh
How RapidMX stacks up
RapidMX focuses on communication: mail, scheduling and meetings. If that's what you rely on Google Workspace or Microsoft 365 for, here's what changes when switch to RapidMX.
| RapidMX | Google Workspace | Microsoft 365 | |
|---|---|---|---|
| Runs on servers you control | Yes | NoProvider cloud only | NoProvider cloud only |
| Source code you can read and audit | YesMPL-2.0 | No | No |
| Licensing | YesFree, any number of users | NoPer user, per month | NoPer user, per month |
| You choose where data is stored | YesAny country, any host | PartlyData regions on some plans | PartlyData residency on some plans |
| End-to-end encryption for every user | YesS/MIME, built in | PartlyClient-side encryption on top tiers | PartlyS/MIME with your own PKI |
| Mail, calendar, contacts and tasks | Yes | Yes | Yes |
| Video meetings | Yesvia Plugin | Yes | Yes |
| Booking pages | Yesvia Plugin | Yes | Yes |
| Works with existing apps | YesExchange ActiveSync | Yes | Yes |
| Retention, legal hold and eDiscovery | YesIncluded | PartlyHigher tiers | PartlyHigher tiers |
| Extend with your own plugins | Yesnpm packages | PartlyMarketplace add-ons | PartlyAdd-ins |
| Documents, spreadsheets and file storage | NoComing soon | Yes | Yes |
Based on publicly available plan information as of 2026. Features and plans of other providers change; check with them for current details. Google Workspace and Microsoft 365 are trademarks of their respective owners.
Built in the open, made to be extended
RapidMX is written in TypeScript using the RapidREST framework, with a React-based web client and Tauri-based desktop/mobile app. The plugin system lets you expand the server's capabilities. Exchange ActiveSync, booking pages and video meetings are all plugins themselves.
Questions, answered
Is RapidMX really free?
Yes. RapidMX is open-source software under the Mozilla Public License 2.0, with no per-user fees and no paid tiers or subscriptions. Your costs are the server, storage and bandwidth you run it on.
What do I need to run it?
A domain name and a Linux server with a public IP address and about 8 GiB of memory is enough for the one-command installer. You'll need port 25 open for mail, which some hosting providers block by default. See Before you deploy.
Do I need to know Kubernetes?
No. The single-server installer sets up and manages a small single-node Kubernetes (k3s) cluster for you. If you already run a cluster, the Helm chart fits right in.
Can I move my existing mail over from Gmail or Outlook?
Yes. RapidMX imports mailboxes from mbox files (what Google Takeout exports) and Outlook PST files. See Import and export.
Will my team have to change apps?
For most people, no. The built-in mail apps on Android, iOS, and Windows connect through Exchange ActiveSync. Support for Outlook for Windows, over MAPI over HTTP, is still being finished. The built-in web app works in any modern browser. RapidMX does not support IMAP or POP3.
Can my administrator read my email?
Administrators manage the platform: domains, policies, plugins and branding. They don't see other people's mail in the app. Getting into someone else's mailbox takes a deliberate action that is recorded in the audit log, and encrypted messages stay unreadable without the owner's key unless your organization has set up key escrow, which itself requires multiple approvers.
What happens if I forget my encryption password?
When you set up encryption you're given recovery codes, Keep the codes somewhere safe: they're the way back in. See Encryption.
Does RapidMX replace Google Docs or OneDrive?
No. RapidMX focuses on communication: mail, calendar, contacts, tasks, meetings, booking and CRM. It pairs well with any self-hosted or cloud document and file service you prefer.
Is it ready for production?
RapidMX is in public beta on its way to 1.0. It runs real mail for real domains today, and releases ship frequently. As with any mail server, keep backups and read the upgrade notes before each update.
Take back your inbox.
Set up your own RapidMX server and send your first message today.