MailHog Save

Web and API based SMTP testing

Project README

MailHog Download GoDoc Build Status

Inspired by MailCatcher, easier to install.

  • Download and run MailHog
  • Configure your outgoing SMTP server
  • View your outgoing email in a web UI
  • Release it to a real mail server

Built with Go - MailHog runs without installation on multiple platforms.


MailHog is an email testing tool for developers:

  • Configure your application to use MailHog for SMTP delivery
  • View messages in the web UI, or retrieve them with the JSON API
  • Optionally release messages to real SMTP servers for delivery


Manual installation

Download the latest release for your platform. Then read the deployment guide for deployment options.


brew update && brew install mailhog

Then, start MailHog by running mailhog in the command line.

Debian / Ubuntu Go < v1.18

sudo apt-get -y install golang-go
go get

Go >= v1.17 (Debian Bookworm)

sudo apt-get -y install golang-go
go install

Then, start MailHog by running /path/to/MailHog in the command line.

E.g. the path to Go's bin files on Ubuntu is ~/go/bin/, so to start the MailHog run:



pkg install mailhog
sysrc mailhog_enable="YES"
service mailhog start


Run it from Docker Hub or using the provided Dockerfile


Check out how to configure MailHog, or use the default settings:

  • the SMTP server starts on port 1025
  • the HTTP server starts on port 8025
  • in-memory message storage


See MailHog libraries for a list of MailHog client libraries.

  • ESMTP server implementing RFC5321
  • Support for SMTP AUTH (RFC4954) and PIPELINING (RFC2920)
  • Web interface to view messages (plain text, HTML or source)
    • Supports RFC2047 encoded headers
  • Real-time updates using EventSource
  • Release messages to real SMTP servers
  • Chaos Monkey for failure testing
  • HTTP API to list, retrieve and delete messages
    • See APIv1 and APIv2 documentation for more information
  • HTTP basic authentication for MailHog UI and API
  • Multipart MIME support
  • Download individual MIME parts
  • In-memory message storage
  • MongoDB and file based storage for message persistence
  • Lightweight and portable
  • No installation required


mhsendmail is a sendmail replacement for MailHog.

It redirects mail to MailHog using SMTP.

You can also use MailHog sendmail ... instead of the separate mhsendmail binary.

Alternatively, you can use your native sendmail command by providing -S, for example:

/usr/sbin/sendmail -S mail:1025

For example, in PHP you could add either of these lines to php.ini:

sendmail_path = /usr/local/bin/mhsendmail
sendmail_path = /usr/sbin/sendmail -S mail:1025

Web UI

Screenshot of MailHog web interface


MailHog is a rewritten version of MailHog, which was born out of M3MTA.

Clone this repository to $GOPATH/src/ and type make deps.

See the Building MailHog guide.

Requires Go 1.4+ to build.

Run tests using make test or goconvey.

If you make any changes, run go fmt ./... before submitting a pull request.


Copyright ©‎ 2014 - 2017, Ian Kent (

Released under MIT license, see LICENSE for details.

Open Source Agenda is not affiliated with "MailHog" Project. README Source: mailhog/MailHog
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