# Mailpit - email testing for developers ![Tests](https://github.com/axllent/mailpit/actions/workflows/tests.yml/badge.svg) ![Build status](https://github.com/axllent/mailpit/actions/workflows/release-build.yml/badge.svg) ![Docker builds](https://github.com/axllent/mailpit/actions/workflows/build-docker.yml/badge.svg) ![CodeQL](https://github.com/axllent/mailpit/actions/workflows/codeql-analysis.yml/badge.svg) [![Go Report Card](https://goreportcard.com/badge/github.com/axllent/mailpit)](https://goreportcard.com/report/github.com/axllent/mailpit) Mailpit is a multi-platform email testing tool & API for developers. It acts as both an SMTP server, and provides a web interface to view all captured emails. It also contains an API for automated integration testing. Mailpit is inspired by [MailHog](#why-rewrite-mailhog), but modern and much, much faster. ![Mailpit](https://raw.githubusercontent.com/axllent/mailpit/develop/docs/screenshot.png) ## Features - Runs entirely from a single binary, no installation required - SMTP server (default `0.0.0.0:1025`) - Web UI to view emails (formatted HTML, highlighted HTML source, text, headers, raw source and MIME attachments including image thumbnails) - HTML check to test & score mail client compatibility with HTML emails - Light & dark web UI theme with auto-detect - Mobile and tablet HTML preview toggle in desktop mode - Advanced mail search ([see wiki](https://github.com/axllent/mailpit/wiki/Mail-search)) - Message tagging ([see wiki](https://github.com/axllent/mailpit/wiki/Tagging)) - Real-time web UI updates using web sockets for new mail - Optional browser notifications for new mail (when accessed via either HTTPS or `localhost` only) - Configurable automatic email pruning (default keeps the most recent 500 emails) - Email storage either in a temporary or persistent database ([see wiki](https://github.com/axllent/mailpit/wiki/Email-storage)) - Fast SMTP processing & storing - approximately 70-100 emails per second depending on CPU, network speed & email size, easily handling tens of thousands of emails - SMTP relaying / message release - relay messages via a different SMTP server including an optional allowlist of accepted recipients ([see wiki](https://github.com/axllent/mailpit/wiki/SMTP-relay)) - Optional SMTP with STARTTLS & SMTP authentication, including an "accept anything" mode ([see wiki](https://github.com/axllent/mailpit/wiki/SMTP-with-STARTTLS-and-authentication)) - Optional HTTPS for web UI ([see wiki](https://github.com/axllent/mailpit/wiki/HTTPS)) - Optional basic authentication for web UI ([see wiki](https://github.com/axllent/mailpit/wiki/Basic-authentication)) - A simple REST API ([see docs](docs/apiv1/README.md)) - Multi-architecture [Docker images](https://github.com/axllent/mailpit/wiki/Docker-images) ## Installation The Mailpit web UI listens by default on `http://0.0.0.0:8025`, and the SMTP port on `0.0.0.0:1025`. Mailpit runs as a single binary and can be installed in different ways: ### Install via Brew (Mac) Install Mailpit with `brew install mailpit`. ### Install via bash script (Linux & Mac) Linux & Mac users can install it directly to `/usr/local/bin/mailpit` with: ```bash sudo bash < <(curl -sL https://raw.githubusercontent.com/axllent/mailpit/develop/install.sh) ``` ### Download static binary (Windows, Linux and Mac) Static binaries can always be found on the [releases](https://github.com/axllent/mailpit/releases/latest). The `mailpit` binary can extracted and copied to your `$PATH`, or simply run as `./mailpit`. ### Docker See [Docker instructions](https://github.com/axllent/mailpit/wiki/Docker-images) for 386, amd64 & arm64 images. ### Compile from source To build Mailpit from source see [building from source](https://github.com/axllent/mailpit/wiki/Building-from-source). ## Usage Run `mailpit -h` to see options. More information can be seen in [the docs](https://github.com/axllent/mailpit/wiki/Runtime-options). ### Testing Mailpit Please refer to [the documentation](https://github.com/axllent/mailpit/wiki/Testing-Mailpit) of how to easily test email delivery to Mailpit. ### Configuring sendmail Mailpit's SMTP server (by default on port 1025), so you will likely need to configure your sending application to deliver mail via that port. A common MTA (Mail Transfer Agent) that delivers system emails to a SMTP server is `sendmail`, used by many applications including PHP. Mailpit can also act as substitute for sendmail. For instructions of how to set this up, please refer to the [sendmail documentation](https://github.com/axllent/mailpit/wiki/Configuring-sendmail). ## Why rewrite MailHog? I had been using MailHog for a few years to intercept and test emails, but experienced a number of severe performance issues. Many of the frontend and Go libraries are very out of date, and the project [is no longer maintained](https://github.com/mailhog/MailHog/issues/442#issuecomment-1493415258). Initially I tried to upgrade a fork of MailHog (the UI, the HTTP server and the API), but discovered that it is (with all due respect to its authors) far too complex. I found it over-engineered (split over 9 separate projects), and performs very poorly when dealing with large amounts of emails or emails with attachments (a single email with a 3MB attachment can take over a minute to ingest). Finally the API transmits a lot of duplicate & irrelevant data on every browser request, all without any HTTP compression. In order to improve it I felt it needed to be completely rewritten, and so Mailpit was born.