Mailpit - email testing for developers

**Mailpit** is a small, fast, low memory, zero-dependency, multi-platform email testing tool & API for developers. It acts as an SMTP server, provides a modern web interface to view & test captured emails, and includes an API for automated integration testing. Mailpit was originally **inspired** by MailHog which is [no longer maintained](https://github.com/mailhog/MailHog/issues/442#issuecomment-1493415258) and hasn't seen active development or security updates for a few years now. ![Mailpit](https://raw.githubusercontent.com/axllent/mailpit/develop/server/ui-src/screenshot.png) ## Features - Runs entirely from a single [static binary](https://mailpit.axllent.org/docs/install/) or multi-architecture [Docker images](https://mailpit.axllent.org/docs/install/docker/) - Modern web UI with advanced [mail search](https://mailpit.axllent.org/docs/usage/search-filters/) to view emails (formatted HTML, highlighted HTML source, text, headers, raw source, and MIME attachments including image thumbnails), including optional [HTTPS](https://mailpit.axllent.org/docs/configuration/http/) & [authentication](https://mailpit.axllent.org/docs/configuration/http/) - [SMTP server](https://mailpit.axllent.org/docs/configuration/smtp/) with optional STARTTLS or SSL/TLS, authentication (including an "accept any" mode) - A [REST API](https://mailpit.axllent.org/docs/api-v1/) for integration testing - Real-time web UI updates using web sockets for new mail & optional [browser notifications](https://mailpit.axllent.org/docs/usage/notifications/) when new mail is received - Optional [POP3 server](https://mailpit.axllent.org/docs/configuration/pop3/) to download captured message directly into your email client - [HTML check](https://mailpit.axllent.org/docs/usage/html-check/) to test & score mail client compatibility with HTML emails - [Link check](https://mailpit.axllent.org/docs/usage/link-check/) to test message links (HTML & text) & linked images - [Spam check](https://mailpit.axllent.org/docs/usage/spamassassin/) to test message "spamminess" using a running SpamAssassin server - [Create screenshots](https://mailpit.axllent.org/docs/usage/html-screenshots/) of HTML messages via web UI - Mobile and tablet HTML preview toggle in desktop mode - [Message tagging](https://mailpit.axllent.org/docs/usage/tagging/) including manual tagging or automated tagging using filtering and "plus addressing" - [SMTP relaying](https://mailpit.axllent.org/docs/configuration/smtp-relay/) (message release) - relay messages via a different SMTP server including an optional allowlist of accepted recipients - Fast message [storing & processing](https://mailpit.axllent.org/docs/configuration/email-storage/) - ingesting 100-200 emails per second over SMTP depending on CPU, network speed & email size, easily handling tens of thousands of emails, with automatic email pruning (by default keeping the most recent 500 emails) - `List-Unsubscribe` syntax validation - Optional [webhook](https://mailpit.axllent.org/docs/integration/webhook/) for received messages ## 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 package managers - **Mac**: `brew install mailpit` (to run automatically in the background: `brew services start mailpit`) - **Arch Linux**: available in the AUR as `mailpit` - **FreeBSD**: `pkg 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 be extracted and copied to your `$PATH`, or simply run as `./mailpit`. ### Docker See [Docker instructions](https://mailpit.axllent.org/docs/install/docker/) for 386, amd64 & arm64 images. ### Compile from source To build Mailpit from source, see [Building from source](https://mailpit.axllent.org/docs/install/source/). ## Usage Run `mailpit -h` to see options. More information can be seen in [the docs](https://mailpit.axllent.org/docs/configuration/runtime-options/). If installed using homebrew, you may run `brew services start mailpit` to always run mailpit automatically. ### Testing Mailpit Please refer to [the documentation](https://mailpit.axllent.org/docs/install/testing/) on how to easily test email delivery to Mailpit. ### Configuring sendmail Mailpit's SMTP server (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 an SMTP server is `sendmail`, used by many applications, including PHP. Mailpit can also act as substitute for sendmail. For instructions on how to set this up, please refer to the [sendmail documentation](https://mailpit.axllent.org/docs/install/sendmail/).