Browse free open source Email software and projects for Mac and Linux below. Use the toggles on the left to filter open source Email software by OS, license, language, programming language, and project status.

  • The All-in-One Commerce Platform for Businesses - Shopify Icon
    The All-in-One Commerce Platform for Businesses - Shopify

    Shopify offers plans for anyone that wants to sell products online and build an ecommerce store, small to mid-sized businesses as well as enterprise

    Shopify is a leading all-in-one commerce platform that enables businesses to start, build, and grow their online and physical stores. It offers tools to create customized websites, manage inventory, process payments, and sell across multiple channels including online, in-person, wholesale, and global markets. The platform includes integrated marketing tools, analytics, and customer engagement features to help merchants reach and retain customers. Shopify supports thousands of third-party apps and offers developer-friendly APIs for custom solutions. With world-class checkout technology, Shopify powers over 150 million high-intent shoppers worldwide. Its reliable, scalable infrastructure ensures fast performance and seamless operations at any business size.
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  • Simple, Secure Domain Registration Icon
    Simple, Secure Domain Registration

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    Register or renew your domain and pay only what we pay. No markups, hidden fees, or surprise add-ons. Choose from over 400 TLDs (.com, .ai, .dev). Every domain is integrated with Cloudflare's industry-leading DNS, CDN, and free SSL to make your site faster and more secure. Simple, secure, at-cost domain registration.
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  • 1
    SquirrelMail
    SquirrelMail is a PHP-based Web email client. It includes built-in pure PHP support for IMAP and SMTP, and renders all pages in pure HTML 4.0 for maximum compatibility across browsers. It has strong MIME support and a flexible plugin system.
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    Downloads: 601 This Week
    Last Update:
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  • 2
    phpList

    phpList

    Powerful Open Source Email Marketing app with analytics & segmentation

    phpList delivers Open Source email marketing, including analytics, list segmentation, content personalisaton and bounce processing. Extensive technical features and a secure and stable codebase are the result of over 17 years of continuous development. Used in 95 countries, available in 20+ languages, and used to send 25 billion email campaigns last year. Deploy it with your own SMTP server, or get a free hosted account at http://phplist.com.
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    Downloads: 238 This Week
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  • 3
    MsgViewer
    MsgViewer is email-viewer utility for .msg e-mail messages, implemented in pure Java. MsgViewer works on Windows/Linux/Mac Platforms. Also provides a java api to read mail messges (msg files) programmatically.
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    Downloads: 159 This Week
    Last Update:
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  • 4
    PostfixAdmin
    PostfixAdmin is a Web Based Management tool created for Postfix. It is a PHP based application that handles Postfix Style Virtual Domains and Users that are stored in MySQL, PostgreSQL or SQLite
    Downloads: 63 This Week
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  • Gen AI apps are built with MongoDB Atlas Icon
    Gen AI apps are built with MongoDB Atlas

    Build gen AI apps with an all-in-one modern database: MongoDB Atlas

    MongoDB Atlas provides built-in vector search and a flexible document model so developers can build, scale, and run gen AI apps without stitching together multiple databases. From LLM integration to semantic search, Atlas simplifies your AI architecture—and it’s free to get started.
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  • 5
    vtenext - Holistic CRM (CRM + BPM + AI)
    vtenext, holistic CRM is not for you if you are looking for: - a classic CRM separated by departments, a copy of the closed source CRM but open source - a solution that permit to you to avoid to pay any kind of support for the CRM of your company - a second choice CRM, cause you have not enough budget for the closed source. So please, save time and save energy. Don’t DOWLOAD VTE If you are looking for: - a new age of CRM applications - a solution that has the right balance between performance and user licenses - an holistic application that manage all the customer processes, including the internal customers Please go on and have fun. For any support feel free to contact us and to have more information regarding the installation procedure visit: http://usermanual.vtenext.com/books/installation-requirements/page/installation-requirements-vtenext-1812
    Downloads: 23 This Week
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  • 6
    FUDforum
    FUDforum is a super fast and scalable discussion forum. It is highly customizable and supports unlimited members, forums, posts, topics, polls & attachments. It can import XML Feeds and sync with USENET groups and Mailing Lists (bi-directional).
    Downloads: 15 This Week
    Last Update:
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  • 7

    PHP Address Book

    Simple, web-based address & phone book

    Simple, web-based address & phone book, contact manager, organizer. Groups, addresses, e-Mails, phone numbers & birthdays. vCards, LDIF, Excel, iPhone, Gmail & Google-Maps supported. PHP / MySQL based.
    Downloads: 12 This Week
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  • 8
    NOCC
    NOCC is a simple and fast Webmail client which can handle POP3 and IMAP mailboxes and sends email via SMTP. It is written with PHP, has low requirements (no database, frames). Features multi-language support, MIME attachments, displays HTML messages. The installation guide comes with the source code: https://sourceforge.net/p/nocc/code/HEAD/tree/trunk/webmail/docs/INSTALL If you encounter problems or bugs you can always try the current HEAD version: https://sourceforge.net/p/nocc/code/HEAD/tarball?path= Questions, bug reports or support requests are very welcome: https://sourceforge.net/p/nocc/_list/tickets Alternative source code repository: https://github.com/oheil/NOCC
    Downloads: 14 This Week
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  • 9
    SaltOS

    SaltOS

    SaltOS, ERP, CRM, Business Management Suite, Josep Sanz Campderrós

    SaltOS is a Business Management solution 100% Cloud Computing. It integrates features like CRM (Customer Relation Management) and ERP (Enterprise Resource Planning). Moreover is it licensed as 100% free software GPL-3.0.
    Downloads: 8 This Week
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  • Enterprise and Small Business CRM Solution | Clear C2 C2CRM Icon
    Enterprise and Small Business CRM Solution | Clear C2 C2CRM

    Voted Best CRM System with Top Ranked Customer Support. CRM Management includes Sales, Marketing, Relationship Management, and Help Desk.

    C2CRM consists of four modules that integrate to provide a comprehensive CRM solution: Relationship Management, Sales Automation, Marketing Automation, and Customer Service. Only buy what each user needs.
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  • 10
    CuteFlow is a webbased document circulation/workflow tool. Users are able to define "documents" which are send step by step to every user in a list. It's an electronical way for doing (i.e. internal) document circulations.
    Downloads: 4 This Week
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  • 11

    Outlook LookForDuplicates

    Find and remove duplicate items in Outlook such as contacts and mails.

    Find&remove duplicates easily! This VBA-Script with a form searches for duplicate entries of any type (calendar, contact, e-mail, notes, task, etc.) across folders in Outlook. Suspected doublets are listed and can be moved to the folder for Deleted Items.
    Downloads: 4 This Week
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  • 12
    GoldBug - Encrypted Communications

    GoldBug - Encrypted Communications

    Chat Messenger. E-Mail-Client. Websearch. Filetransfer.

    GoldBug is a decentralized & secure communication suite that offers an integrated e-mail client, an instant messenger & a file transfer. Also included is an URL-RSS-DB & a p2p web search. Current vers. w/ McEliece Algorithm. GoldBug has been 2013 - 2023 ten years just another Graphical User Interface of the Spot-On Encryption Suite. Main GUI features: Minimal & colorful Interface with Tabs in the East. Microsoft & Qt MinGW deprecated Win32 & for Compiling: ● https://sourceforge.net/p/goldbug/wiki/compiling As Spot-On implemented the minimal GB-concept & Nuvola Icons, GoldBug has now been fully integrated into Spot-On Win64: Just choose Tabs at East & Mini-View in Options - w/ Nuvola Icons of course! Voilá! & Many Thanks, Pro-Files can be found archived at ● current source: https://github.com/textbrowser/spot-on ● EN Manual: https://www.amazon.com/dp/3749435065 ● DE: https://compendio.github.io/goldbug-manual-de/ ● Study: https://www.amazon.com/asin/dp/3750408971
    Downloads: 14 This Week
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  • 13
    POPFile - Automatic Email Classification
    POPFile is an email classification tool with a Naive Bayes classifier, POP3, SMTP, NNTP proxies and IMAP filter and a web interface. It runs on most platforms and with most email clients.
    Downloads: 3 This Week
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  • 14
    Columba
    Columba is an email client written in Java, featuring a user-friendly graphical interface with wizards and internalionalization support. Its a powerful mail management tool with features to enhance your productivity and communication.
    Downloads: 3 This Week
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  • 15
    Lurker is a mailing list archiver designed for capacity, speed, simplicity, and configurability in that order. Noteworthy features include: google-style searching on all fields, chronology preserving threads, multilingual, and attachment support.
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    Downloads: 8 This Week
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  • 16
    Kalkun
    Kalkun is an open source web-based SMS (Short Message Service) manager. It uses Gammu SMSD (part of gammu family) as SMS gateway engine to deliver and retrieve messages from your phone/modem. Documentation is on the wiki: https://github.com/kalkun-sms/Kalkun/wiki Development and source code can be found on github: https://github.com/kalkun-sms/Kalkun/
    Downloads: 2 This Week
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  • 17
    IlohaMail is a PHP based lightweight full featured multilingual webmail program with IMAP and POP3 support. IlohaMail also includes a full-featured contacts manager, bookmarks manager, and scheduler.
    Downloads: 4 This Week
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  • 18
    mailredirect

    mailredirect

    Allow to redirect (a.k.a. "remail") mail messages to other recipients

    The Mailredirect extension for Mozilla Thunderbird and Mozilla SeaMonkey adds the ability to redirect one or more email messages to one or more recipients. The feature of email redirecting is also known as remailing or resending. The extension is an answer for https://bugzil.la/12916
    Downloads: 4 This Week
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  • 19
    A Club member administration tool written in PHP using a MySQL database. Clubdata is highly configurable, supports different membership types, a lot of membership features, mass e-mails, Excel-export, PDF-export and sophisticated authentication. Club
    Downloads: 1 This Week
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  • 20
    Hastymail
    Hastymail is a fast, secure, rfc-compliant, cross-platform IMAP/SMTP client application written in PHP providing a clean web interface for sending and reading E-mail. This version of Hastymail is no longer being developed. We are now working on a new version, Hastymail 3, AKA, "Cypht". http://cypht.org
    Downloads: 1 This Week
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  • 21
    Codegroup

    Codegroup

    A Java application for transferring computer files in 5 letter groups

    Codegroup is a Java application that will allow one to convert binary (or text) computer files in to 5 letter codegroups for transmission over email, landline telephones, radioteletype or Morse Code. Codegroup has internal error correction & limited cryptography capabilities. Codegroup : ZZZZZ YBPIL AIAIG FMOPP CPAAA DGNGP GPGPA ADNJN ELJKO ELIMO GEOHF KIFGP IFBCB PKCPI YJMHE PHBHP PPOBH NCOHD AKLLL AGHFP DEGEF LKELC EAIJI ABAGP AHPPO IHHPH OHPDF YNFPB ALEPO KMPKP Once this program has a graphical user interface, an Enigma like subsystem must be devised for data whitening. For content encryption, the use of Java's facilities is being considered as a long term option. This project's initial sourcecode is related to : http://www.fourmilab.ch/codegroup/ http://winmorse.com/ https://bitbucket.org/bgneal/cpp-enigma http://www.whence.com/minimodem/ For the User Interface http://www.oracle.com/technetwork/java/javafx/tools/
    Downloads: 2 This Week
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  • 22
    Mailster is a project aimed at testing software mail capabilities. It provides a mail server container to test emails sent by your apps without rewriting your application code.
    Downloads: 2 This Week
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  • 23
    SmartSieve is a web based graphical user interface for creating and managing sieve scripts for mail filtering and vacation messaging on a cyrus imap mail server. Written in PHP, SmartSieve is easy to configure and use.
    Downloads: 2 This Week
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  • 24
    This script can be applied to mbox-files and msg-email files (created by Opera web browser). It converts one or more *.mbox / *.msg files to HTML (including their attachments).
    Downloads: 1 This Week
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  • 25
    ADbNewsSender is an easy to install and use php based newsletter script. You can use it to manage multiple newsletters. It is using double opt in and supports MySQL/MariaDB and PostgreSQL. You can also present a web archive to your website's visitor. Please note that the development has been discontinued. You can still download the software, but you won't receive any support or updates.
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    Downloads: 1 This Week
    Last Update:
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