docker-mailserver vs Mail-in-a-Box (2026): which should you pick?
As of Nov 13, 2026, Mail-in-a-Box grades higher than docker-mailserver: 2.0 against 1.8 out of 4.0.
Checked Nov 13, 2026 · graded Nov 13, 2026 by ToolGPA
docker-mailserver grades higher on the free plan. Mail-in-a-Box grades higher on features and platforms. They get the same grade on value for money and ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
docker-mailserver
Self-hosted mail server packaged as a Docker container
Mail-in-a-Box
Free script that turns a cloud server into your own mail server
Which one is for you
Pick docker-mailserver if
- Fits if you are comfortable with Docker and a config file and want your own mail server
- Works for people who read documentation and fix things themselves
Look elsewhere if
- Not for you if you want a settings page, because setup is by files, variables and the command line
- Skip it if you want paid support, as help comes from the community and the docs
- Too much work if you don't want to handle DNS, TLS certificates and deliverability
- Watch out: the listing shows no webmail or admin screen
Pick Mail-in-a-Box if
- Fits if you want your own mail on your own domain and can run a server
- Works for people who would rather run one script than configure ten programs
Look elsewhere if
- Skip it if you want a home connection to do it, since it needs a cloud server with a clean IP
- Skip it if you don't want to be the sysadmin
- Watch out: the page warns that other mail services may block or filter mail from your own server
- Watch out: it needs a dedicated fresh machine, and manual changes after install are overwritten
How we grade them
| 1.8GPAdocker-mailserverWeak | 2.0GPAMail-in-a-BoxFair | |
|---|---|---|
| Value for money | CFree under MIT, but it only runs on a Docker host you look after, so self-hosted free is a C. | CThe software is free, but the guide puts a server at about $12 a month plus a domain at about $17 a year, which lands in the dearer end of the category. |
| Free plan and trial | BFree outright, no plan limits. You need your own Docker host, so a B and not an A. | CFree software that still needs a rented server running before anything works. |
| Features | CSMTP, IMAP, antispam, antivirus, Sieve and account provisioning in one container. It does the server job but the listing shows no web admin panel or webmail. | BMail server, webmail, automatic DNS and security records, spam filtering, backups, multiple users and domains. The listing shows no gap in the core job. |
| Ease of use | DNo store rating on record. Configuration is by files, environment variables and command-line tools, per its own docs, so a D. | DYou install it on a fresh machine and act as the sysadmin, with help from a forum and chat room. |
| Platforms and integrations | DLinux and Docker only. It connects through Postfix, Dovecot, Rspamd, Fail2Ban and ClamAV and has no apps. | CA web admin and webmail, with Roundcube, Nextcloud and Let's Encrypt. No apps of its own. |
| Best for | a mail server in one Docker container | one script that makes a cloud server a mail server |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: docker-mailserver and Mail-in-a-Box. How we grade
Price against what you get
docker-mailserver has no paid plan and scores 1.3 out of 4 on features, ease of use and platforms. Mail-in-a-Box has no paid plan and scores 2.0.
Mail-in-a-Box scores higher for the same starting price. Of the other email apps on the chart, none scores higher than docker-mailserver for less, and none scores higher than Mail-in-a-Box for less.
Features, ease of use and platforms, averaged
What paid plans start at, a month (each step along is roughly double) →
- The best score at each price
- Has a free plan
- No free plan
Where they differ
- Mail-in-a-Box also covers calendar and email client.
At a glance
| docker-mailserver | Mail-in-a-Box | |
|---|---|---|
| Pricing | Free | Free |
| Starts at | Free | Free |
| Free plan | Free and open source under the MIT license; you run the container yourself. | The software is free; you pay for your own server and domain, which the setup guide puts at about $12 a month plus roughly $17 a year. |
| Free trial | None listed | None listed |
| Web | ||
| Linux | ||
| Made by | docker-mailserver community | Mail-in-a-Box project |
| Price read from | github.com | mailinabox.email |
| Checked | Nov 13, 2026 | Nov 13, 2026 |
Worth knowing
docker-mailserver
- Configuration is done through files, environment variables and command-line tooling, per the documentation.
- Setup and upkeep, including DNS, TLS certificates and deliverability, are on you.
- Support comes from the community and documentation, not a paid plan.
Mail-in-a-Box
- It cannot run on a home connection: it needs a cloud server with a clean IP, so the guide advises renting a virtual machine.
- It must be installed on a fresh machine dedicated to it, and manual changes after install are overwritten.
- The page warns that other mail services may block or spam-filter mail sent from your own server.
- You act as the system administrator and must fix issues yourself; help comes from a forum and chat room.
Key features
docker-mailserver
- All-in-one container
- The GitHub project describes a production-ready, full-stack mail server running inside a container.
- Postfix and Dovecot
- The documentation names Postfix as the MTA and Dovecot as the MDA.
- Spam and malware filtering
- Rspamd and Fail2Ban are documented, along with DKIM, DMARC and SPF setup.
- Account provisioning
- Accounts can come from files or from an LDAP service, and OAuth2 authentication is documented.
- Sieve filtering
- Email filtering with Sieve is documented, plus a forward-only mode with LDAP.
Mail-in-a-Box
- Webmail and mail server in one
- Includes Roundcube webmail and an IMAP and SMTP server for phones and desktop mail apps, with contacts and calendar sync.
- Automatic DNS and security records
- When the box acts as your nameserver it sets SPF, DKIM, DMARC and MTA-STS records, and can add DNSSEC with DANE.
- Control panel and API
- A web panel to add mail accounts, aliases and custom DNS records, run status checks and set up backups, also reachable over a REST API.
- Spam filtering and backups
- Spam filtering with greylisting, mail filter rules, TLS certificates from Let's Encrypt and automated backups to Amazon S3 and similar services.
- Multiple users and domains
- One box can host mail for several users and domain names, with simple static website hosting on the side.
Plans
docker-mailserver
Free$0
Open source under the MIT license. Run it on your own Docker host.
Mail-in-a-Box
Mail-in-a-Box$0
Free software. The setup guide estimates about $12 a month for the cloud server, plus a domain name at about $17 a year.
Common questions
Which is cheaper, docker-mailserver or Mail-in-a-Box?
As of Nov 13, 2026, both docker-mailserver and Mail-in-a-Box are free to use.
Which has a free plan, docker-mailserver or Mail-in-a-Box?
As of Nov 13, 2026, both docker-mailserver and Mail-in-a-Box have a free plan.
Which platforms do docker-mailserver and Mail-in-a-Box run on?
As of Nov 13, 2026, only docker-mailserver lists a Linux app and only Mail-in-a-Box lists a web app. A platform missing from a listing is one its maker's pages did not mention.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.