Open-source email software
415 open-source libraries, tools and applications tagged email, ranked by how closely email is their primary purpose, then by adoption and maintenance health. Each entry links to a page with sources, use cases and when to choose or avoid it.
415 products, primary matches first, then adoption-weighted; health v2 shown.
| Product | Health v2 | Stars | Maturity |
|---|---|---|---|
| sabuhish/fastapi-mail Fastapi-mail is a lightweight Python library for sending emails from FastAPI applications, supporting individual and bulk messages, attachm… | 93 | 1013 | active |
| typpo/textbelt TextBelt Open Source is a REST API and Node.js/Express server that sends outgoing SMS for free using carrier-specific email-to-SMS gateways… | 32 | 3393 | maintenance |
| leemunroe/grunt-email-workflow A Grunt-based build workflow for designing and testing responsive HTML email templates using SCSS. It compiles SCSS to CSS, builds HTML ema… | 32 | 3034 | maintenance |
| flashmob/go-guerrilla Go-Guerrilla is a lightweight SMTP server daemon written in Go, designed for receiving large volumes of email quickly and efficiently. It c… | 23 | 2964 | maintenance |
| jordan-wright/email A Go library for composing and sending email over SMTP with a simple, human-friendly API. It supports text and HTML bodies, attachments, cu… | 23 | 2791 | maintenance |
| MailCore/mailcore2 MailCore 2 is a C++/Objective-C library providing a simple, asynchronous API for working with email protocols IMAP, POP, and SMTP. It inclu… | 67 | 2698 | maintenance |
| mangini/gdocs2md A Google Apps Script that converts a formatted Google Drive Document into Markdown, emailing the converted file with extracted images as at… | 32 | 2660 | maintenance |
| helpyio/helpy Helpy is an open source, self-hosted helpdesk and customer support platform built with Ruby on Rails. It combines support ticketing integra… | 23 | 2469 | maintenance |
| Baiyuetribe/kamiFaka kamiFaka is a self-hosted card-key (kami) vending system for selling virtual goods like activation codes, coupons, and invite codes, built … | 23 | 2319 | maintenance |
| sensepost/ruler Ruler is a Go-based command-line tool for interacting with and abusing Microsoft Exchange servers via MAPI/HTTP or RPC/HTTP. It enables off… | 23 | 2310 | maintenance |
| mscdex/node-imap node-imap is an IMAP client module for Node.js that lets applications connect to IMAP mail servers, list mailboxes, and fetch messages and … | 32 | 2221 | maintenance |
| emersion/hydroxide Hydroxide is a third-party, open-source ProtonMail bridge written in Go that translates standard protocols (IMAP, SMTP, CardDAV) into Proto… | 10 | 2169 | maintenance |
| Flolagale/mailin Mailin is an SMTP server that receives inbound emails, parses them, and posts them as JSON to a webhook URL of your choice. It also validat… | 23 | 1954 | maintenance |
| OfflineIMAP/offlineimap OfflineIMAP is a Python command-line tool that synchronizes IMAP mailboxes to local Maildir folders, enabling offline email reading and ind… | 23 | 1860 | maintenance |
| xuhuai66/used-book-pro A fully open-source WeChat mini-program for a campus second-hand book marketplace, built on WeChat cloud development (cloud functions and c… | 32 | 1823 | maintenance |
| chenjj/espoofer espoofer is a Python-based testing tool that crafts spoofed emails to bypass SPF, DKIM, and DMARC authentication, including forged DKIM sig… | 32 | 1755 | maintenance |
| nodemailer/mailparser An advanced email parser for Node.js that decodes MIME-formatted emails, handling everything as streams to parse very large messages with l… | 96 | 1670 | maintenance |
| g13nn/Email-Framework A responsive HTML email framework providing boilerplates, grid systems, components, and snippets for building HTML email templates. It supp… | 32 | 1668 | maintenance |
| mailgun/flanker Flanker is a Python library by Mailgun for parsing email addresses and MIME messages. It provides robust address parsing (single addresses … | 64 | 1647 | maintenance |
| mailboxer/mailboxer Mailboxer is a Ruby on Rails gem that adds a private messaging system to web applications. It supports multi-participant conversations, sys… | 23 | 1633 | maintenance |
| Cloudflare Email Sending A Cloudflare Workers-based proxy server for sending free transactional emails via the MailChannels API. It exposes an authenticated HTTP en… | 51 | 1600 | maintenance |
| denghongcai/forsaken-mail Forsaken Mail is a self-hosted disposable email service that lets you receive emails at temporary addresses via a built-in SMTP server and … | 32 | 1552 | maintenance |
| Raikia/FiercePhish FiercePhish is a self-hosted PHP web application for managing full phishing engagements, including campaign tracking, scheduled email sendi… | 23 | 1437 | maintenance |
| hongyonghan/Docker_Microsoft365_E5_Renew_X A Dockerized deployment of Microsoft 365 E5 Renew X, a service that keeps Microsoft 365 Developer (E5) subscriptions active by periodically… | 32 | 1377 | maintenance |
| Roadie A Ruby gem that makes HTML emails easier by inlining stylesheets into the markup and rewriting relative URLs to absolute ones. It handles e… | 76 | 1349 | maintenance |
| basecamp/mail_view MailView is a Ruby gem that lets Rails developers preview plain text and HTML email templates in a browser without actually sending mail. I… | 10 | 1321 | maintenance |
| muan/github-gmail A browser extension for Chrome and Firefox that adds keyboard shortcuts to Gmail for opening and muting GitHub notification emails. It stre… | 23 | 1265 | maintenance |
| Resend Email Platform React Email is a collection of high‑quality, unstyled React components for building email templates. It lets developers write emails using … | 80 | 399 | active |
| beyondcode/laravel-mailbox A Laravel package that lets applications catch and react to incoming emails from services like Mailgun, SendGrid, and Postmark, or a local … | 65 | 1135 | maintenance |
| Hedwig Hedwig is a Swift package providing high-level APIs for sending email through any SMTP server, supporting plain, SSL, and STARTTLS connecti… | 53 | 1123 | maintenance |
| peterbe/premailer A Python library that transforms HTML email markup by converting <style> blocks and external stylesheets into inline style attributes on ea… | 32 | 1082 | maintenance |
| Slicejack/bojler Bojler is an email framework for developing responsive, lightweight HTML email templates that render correctly across popular email clients… | 23 | 1051 | maintenance |
| trumail/trumail Trumail is a free, open-source email verification system written in Go that checks address deliverability via SMTP handshakes with mail ser… | 10 | 1051 | maintenance |
| timeoff-management/timeoff-management-application TimeOff.Management is a self-hostable web application for managing employee absences, leave requests, and PTO for small and medium business… | 23 | 1044 | maintenance |
| Nilhcem/FakeSMTP FakeSMTP is a free, cross-platform dummy SMTP server with a graphical interface, written in Java, that intercepts emails sent by applicatio… | 10 | 1008 | maintenance |
| thunderbird/thunderbird-ios Thunderbird for iOS is an open-source email client for iOS devices, developed from the ground up by the Thunderbird/Mozilla community. It i… | 65 | 1219 | experimental |
| Vue Email Vue Email is a library of unstyled Vue components and render utilities for building email templates with Vue 3 and TypeScript, inspired by … | 53 | 1089 | experimental |
| swiftmailer/swiftmailer Swift Mailer is a component-based, object-oriented PHP library for composing and sending emails via SMTP or Sendmail, with MIME message bui… | 10 | 9423 | abandoned |
| Rambox Rambox Community Edition is a free, open-source, cross-platform desktop app that combines common web messaging and email services (WhatsApp… | 10 | 6380 | abandoned |
| nylas/sync-engine The Nylas Sync Engine is an open-source email sync platform that exposes a RESTful API on top of IMAP/SMTP, letting applications read and s… | 10 | 3494 | abandoned |
| djyde/cusdis Cusdis is an open-source, lightweight (~5kb gzipped) and privacy-friendly embeddable comment system for small websites, designed as a Disqu… | 10 | 2778 | abandoned |
| Formspree Formspree is a form-to-email backend service that lets static sites submit HTML forms by pointing the form action at a Formspree URL, with … | 10 | 2751 | abandoned |
| laudspeaker/laudspeaker Laudspeaker is an open-source customer engagement and product onboarding platform with a visual journey builder, user segmentation, and mul… | 60 | 2628 | abandoned |
| CrimsonForge-io/king-phisher King Phisher is a phishing campaign toolkit for testing and promoting user awareness by simulating real-world phishing attacks, with contro… | 62 | 2602 | abandoned |
| Thomas101/wmail WMail is a free, open-source Electron-based desktop client for Gmail and Google Inbox, supporting multiple accounts, desktop notifications,… | 10 | 2045 | abandoned |
| haskellcamargo/gemidao-do-zap A Node.js command-line application that places phone calls (or sends SMS) to a victim playing the Brazilian meme audio 'gemidão do Zap', op… | 23 | 1975 | abandoned |
| charlierguo/gmail A Python library providing a Pythonic interface to Gmail via IMAP, supporting searching, reading, sending, labeling, archiving, and deletin… | 32 | 1810 | abandoned |
| Proton Mail The official Proton Mail Android email client, an open-source app providing encrypted email access on Android. This repository has been arc… | 10 | 1727 | abandoned |
| fossasia/fossasia-nodemailer A small Node.js server that sends emails via the nodemailer library, configured with a Gmail account. It exposes a web interface on localho… | 32 | 1534 | abandoned |
| symfony/swiftmailer-bundle A Symfony bundle integrating the Swiftmailer library for sending emails in Symfony applications. It is no longer maintained because Swiftma… | 10 | 1534 | abandoned |
| skerkour/bloom Bloom is an open-source, privacy-focused productivity suite offering email inbox, calendar, files, and contacts as a self-hosted alternativ… | 70 | 1530 | abandoned |
| billzhong/inbox.py Inbox.py is a minimal asynchronous SMTP server library for Python that lets applications receive email with a simple decorator-based handle… | 32 | 1501 | abandoned |
| seven1m/onebody OneBody is an open-source, web-based member portal for churches built with Ruby on Rails and MySQL, offering social networking, email lists… | 10 | 1389 | abandoned |
| ivaldi/brimir Brimir is an open-source email helpdesk/ticketing system built with Ruby on Rails and Zurb Foundation that converts incoming support emails… | 10 | 1363 | abandoned |
| thoughtbot/griddler Griddler is a Rails engine that provides an HTTP endpoint for email delivery services (SendGrid, Cloudmailin, Postmark, Mandrill, Mailgun) … | 10 | 1359 | abandoned |
| zoonk/uneebee Uneebee is an open-source platform for creating interactive courses, similar to Duolingo, built with Elixir, Phoenix LiveView, Postgres, an… | 10 | 1344 | abandoned |
| hardware/mailserver A simple and full-featured mail server distributed as a set of Docker images, bundling Postfix, Dovecot, Rspamd, ClamAV, Sieve, Fetchmail, … | 10 | 1287 | abandoned |
| Zizaco/confide Confide is an authentication package for Laravel 4 that reduces repetitive work in user account management. It provides account creation, l… | 23 | 1180 | abandoned |
| khamidou/kite Kite is a self-hosted webmail client designed to look like Gmail, with an AngularJS frontend and a Python 2 backend, deployable on a single… | 10 | 1061 | abandoned |
| hmailserver/hmailserver hMailServer is an open-source email server for Microsoft Windows providing SMTP, IMAP, and POP3 services. The project is no longer actively… | 98 | 1029 | abandoned |
| manzinello/mailgo A lightweight JavaScript library that transforms all mailto: and tel: links on a webpage into an accessible modal offering direct actions l… | 10 | 1022 | abandoned |
| mjml-react A React component library that wraps MJML markup to generate responsive HTML emails programmatically. It lets developers compose email temp… | 32 | 998 | abandoned |
| Odysseus AI Workspace Odysseus is a self-hosted, privacy-first AI workspace that combines chat, autonomous agents, tools/MCP integration, model serving, and deep… | 57 | 87526 | active |
| Huginn Huginn is a self-hosted system for building agents that perform automated tasks online, such as monitoring websites, watching Twitter, and … | 100 | 50066 | active |
| fastapi/full-stack-fastapi-template A full-stack web application template combining a FastAPI backend with a React frontend, including SQLModel, PostgreSQL, JWT authentication… | 91 | 45973 | active |
| Symfony Symfony is a full-stack PHP framework for building web and console applications, plus a set of reusable, decoupled PHP components used by p… | 93 | 31168 | stable |
| lenve/vhr vhr (微人事) is a full-stack, front-end/back-end separated human resources management system built with Spring Boot and Vue, covering employee… | 32 | 28025 | active |
| Zulip Zulip is an open-source team chat application with unique topic-based threading that combines the best of email and real-time chat. It incl… | 93 | 25994 | stable |
| knadh/listmonk listmonk is a self‑hosted, high‑performance newsletter and mailing‑list manager delivered as a single binary. It provides a web UI, API and… | 90 | 23836 | active |
| Forem Forem is an open‑source Ruby on Rails application for building online communities. It powers sites like dev.to and provides features such a… | 77 | 22796 | active |
| AdonisJS AdonisJS is a TypeScript‑first full‑stack web framework for Node.js that provides a cohesive set of batteries‑included features such as ORM… | 98 | 19142 | active |
| wasp-lang/wasp Wasp is a batteries‑included full‑stack framework that lets you define React, Node.js, and Prisma apps with a single TypeScript spec file. … | 94 | 18752 | active |
| DocuSeal DocuSeal is an open-source, self-hostable web application for creating, filling, and electronically signing PDF documents, positioned as a … | 91 | 18697 | active |
| rowboatlabs/rowboat Rowboat is an open-source desktop AI coworker that indexes your email, meetings, Slack, and conversations into a living backlinked knowledg… | 86 | 17974 | active |
| Apprise Apprise is a Python library and CLI tool that lets you send push notifications to 100+ popular services (Telegram, Discord, Slack, email, S… | 95 | 17607 | stable |
| elie222/inbox-zero Inbox Zero is an open-source AI email assistant web application that organizes your inbox, pre-drafts replies in your voice, blocks cold em… | 97 | 12645 | active |
| Frappe Framework Frappe Framework is a batteries-included, low-code full-stack web application framework written in Python and JavaScript, built around meta… | 95 | 10937 | stable |
| Mail-0/Zero Zero (Mail0) is an open-source, self-hostable email client that unifies multiple providers like Gmail and Outlook into one privacy-first in… | 46 | 10857 | active |
| pocoproject/poco POCO (Portable Components) is a collection of cross-platform C++ class libraries for building network- and internet-centric applications, c… | 94 | 9483 | stable |
| loco-rs/loco Loco is a batteries-included web framework for Rust, strongly inspired by Ruby on Rails and built on Axum and SeaORM. It bundles models, co… | 94 | 9466 | active |
| openclaw/gogcli gog is a single Go binary CLI that provides terminal access to Google Workspace services including Gmail, Calendar, Drive, Docs, Sheets, Sl… | 80 | 8512 | active |
| Cisco-Talos/clamav ClamAV is an open-source antivirus engine and toolkit for detecting trojans, viruses, malware, and other malicious threats. It includes a m… | 92 | 7350 | active |
| hexclave/hexclave Open-source user infrastructure platform handling authentication, teams, RBAC, payments, emails, and analytics for SaaS apps. Deployable as… | 89 | 6868 | active |
| Webhook.site Webhook.site is a tool that instantly generates unique URLs and email addresses to receive, inspect, and debug HTTP webhooks and requests i… | 66 | 6767 | active |
| humhub/humhub HumHub is an open-source (AGPLv3) enterprise social network and intranet collaboration platform written in PHP on the Yii2 framework. It of… | 95 | 6751 | stable |
| Ferry Ferry is an open-source ticketing and workflow engine built with Gin (Go) and Vue + Element UI. It supports configurable approval flows, te… | 34 | 6616 | active |
| filipedeschamps/tabnews.com.br TabNews is the open-source codebase of a Brazilian community website for programming and technology discussions, where users publish posts … | 76 | 6381 | active |
| al1abb/invoify Invoify is a free, web-based invoice generator built with Next.js, TypeScript, React, and shadcn/ui. Users fill in a form, pick from 13 tem… | 69 | 6364 | active |
| maildev/maildev MailDev is a local SMTP server with a modern web interface that catches all emails sent by your application during development, so nothing … | 93 | 6145 | active |
| redmine/redmine Redmine is a flexible, self-hosted project management web application written in Ruby on Rails. It provides issue tracking, wikis, forums, … | 77 | 6050 | stable |
| twisted/twisted Twisted is an event-driven networking engine and framework for Python, providing an asynchronous reactor plus implementations of many inter… | 79 | 5992 | stable |
| Zammad Zammad is a web-based, open-source helpdesk and customer support/ticketing platform that unifies customer communication across channels lik… | 76 | 5974 | stable |
| Faka Card System A self-hosted PHP e-commerce application for selling digital goods and card keys (faka), with an anime/2D-culture themed storefront. It inc… | 99 | 5854 | active |
| AidLux (AidLearning) AidLux (originally AidLearning) is an AIoT development platform that runs a native Ubuntu Linux environment with GUI, deep learning tooling… | 63 | 5812 | active |
| Proton Mail Suite The official monorepo for Proton's web clients, including Proton Mail, Calendar, Drive, VPN, Pass, Wallet, and more. It is built with React… | 82 | 5644 | active |
| umputun/remark42 Remark42 is a self-hosted, privacy-focused comment engine written in Go that can be embedded into blogs and articles. It supports social an… | 100 | 5627 | stable |
| haraka/Haraka Haraka is a fast, highly extensible, event-driven SMTP server written in Node.js with a modular plugin architecture. It is widely deployed … | 93 | 5618 | stable |
| bookorbit/bookorbit BookOrbit is a self-hosted, Docker-native library and reading platform for ebooks, PDFs, comics, and audiobooks. It provides multi-user lib… | 82 | 5513 | active |
| IHP IHP is a batteries-included, type-safe full-stack web framework built on Haskell and Nix, featuring compile-checked HTML (HSX), typed SQL q… | 89 | 5359 | active |
| macro-inc/macro Macro is an open-source all-in-one team workspace that unifies email, chat, docs, tasks, calls, CRM, and AI agents into a single fast inter… | 81 | 4785 | active |