Postfix is described as 'Mail transfer agent (MTA) that routes and delivers electronic mail. It attempts to be fast, easy to administer, and secure. The software is also known by its former names VMailer and IBM Secure Mailer' and is a Mail Server in the online services category. There are more than 25 alternatives to Postfix for a variety of platforms, including Linux, Mac, Windows, Self-Hosted and BSD apps. The best Postfix alternative is Mail-in-a-box, which is both free and Open Source. Other great apps like Postfix are Exim, Mailpit, KumoMTA and MailHog.
Mail-in-a-box is the most popular Self-Hosted alternative to Postfix.
Mail-in-a-box is the most popular Open Source & free alternative to Postfix.
Exim is a message transfer agent (MTA) developed at the University of Cambridge for use on Unix systems connected to the Internet.
Almost everyone thinks Exim is a great Postfix alternative.
Exim is the most popular Mac & Linux alternative to Postfix.
Mailpit is the most popular Windows alternative to Postfix.
KumoMTA is the only true Open-Source PowerMTA alternative, capable of matching performance of several million messages per hour while providing granular traffic shaping configuration and automation across unlimited IPs.
Mailhog is for testing if another application can send mails.
Postfix is for sending and receiving mails.
Some users think MailHog is a great Postfix alternative, some don't.
Stalwart is an open-core mail server solution with JMAP, IMAP4, POP3, and SMTP support and a wide range of modern features. It is written in Rust and designed to be secure, fast, robust and scalable.
Haraka is an open source SMTP server written in Node.js which provides extremely high performance coupled with a flexible plugin system allowing Javascript programmers full access to change the behaviour of the server.
OpenSMTPD is a FREE implementation of the server-side SMTP protocol as defined by RFC 5321, with some additional standard extensions. It allows ordinary machines to exchange e-mails with other systems speaking the SMTP protocol.
Sendmail is a general purpose internetwork email routing facility that supports many kinds of transfer and delivery methods, including the Simple Mail Transfer Protocol (SMTP) used for email transport over the Internet.
The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols, such as ESMTP, IMAP, POP3, LDAP, SSL, and HTTP. Courier provides ESMTP, IMAP, POP3, webmail, and mailing list services within a single, consistent, framework.
sSMTP is a simple MTA to deliver mail from a computer to a mail server. sSMTP is simple and lightweight, there are no daemons or anything hogging up CPU; Just sSMTP. Unlike Exim4, sSMTP does not receive mail, expand aliases, or manage a queue.
A small Mail Transport Agent (MTA), designed for home and office use. Part of DragonFly BSD , it accepts mails from locally installed Mail User Agents (MUA) and delivers the mails either locally or to a remote destination.
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Mail-in-a-box uses Postfix internally