Mailchimp Email Blueprints - Email Blueprints is a collection of HTML email templates that can serve as a solid foundation and starting point for the design of emails.
Antwort - Antwort offers responsive layouts for Email that both fits and adapts to client widths.
Responsive HTML Template - This template is designed to work on all major email platforms and it is built with media query, making it responsive for smartphones that supports media query.
Bulletproof Background Images - Create rock-solid background images for your HTML email with some help from VML and CSS.
Stripo.email - Online drag-n-drop and HTML email builder to create professional and responsive email templates fast without any HTML skills.
MySigMail Card - A free drag & drop builder helps you create email templates intuitively and very quickly.
TestSubject - Test How Your Email Subject Lines Appear On The Most Popular Mobile Devices.
MailSpice analytics - Email analytics add-on for all email services that provides deep insights into all of your email campaigns (works with all ESPs).
Alter.email - A free tool to help you inline CSS, remove unused CSS, clean up your text, add extra attributes to tags, add URL tracking parameters, minify, and even prettify HTML email.
Detergent - A tool to prepare the text for pasting into HTML: removes invisible Unicode characters (like ETX which can come from PSD files), encodes special characters (like turning £ into £) and improves typography.
EmailComb - Email-friendly unused CSS removal tool which does not parse and thus accepts mixed sources, including your ESP templating tags. Extras: CSS uglification and HTML/CSS minification (powered by HTML Crush).
HTML Crush - Email-friendly HTML minifier: limits lines to 500 chars. (best practice), respects Outlook conditional tags and accepts mixed sources, including ESP templating tags. Optionally, can only remove indentations (not touching line breaks).
Tabifier - Opposite of HTML Crush - a tool to beautify the indentation in HTML files. Works with mixed input sources, including your ESP templating tags.
Email Link Builder - Make mailto links that open email drafts with prefilled Recipients, Subject, Body and more.
email-verifier - A tool for email verification without sending any emails.
DevMail - An email sandbox for software developers. Capture emails from your dev, staging, QA, or CI environment.
Disposable Email Check API - A free API for checking if an email address is disposable. No sign up required.
Mailchimp - MailChimp provides email marketing for more than 15 million people globally.
Mailjet - all-in-one Email Services Provider that allows businesses to send Marketing, Transaction Email and Email Automation.
Mailscribe Mailmaker - AI-powered email marketing platform that allows to design email with built-in components.
Campaign monitor - Campaign Monitor makes it easy for you to create, send, and optimize your email marketing campaigns.
Sendgrid - Delivering your transactional and marketing email through one reliable platform.
Postal - A fully featured open source mail delivery platform for incoming & outgoing e-mail.
SparkPost - Your application’s emails: Delivered on time and to the inbox.
Mautic - Mautic Marketing Automation. Build smarter campaigns – and build them faster – with marketing automation that’s quick to learn, simple to use, and easy to iterate.
Mailgun - Transactional Email API Service For Developers.
eSputnik - eSputnik is a marketing automation system trusted by more than 30 thousand loyal customers worldwide to send more than a billion emails every month.
Postmark - Lightning fast delivery for your application emails. Postmark delivers your transactional email to customers on time, every time.
ImprovMX - Create free email aliases for your domain name.
Reacher - Check if an email exists without sending any email. Written in Rust, 100% open-source.
Kickbox - Email verification service (check an email exists).
Forward Email - The 100% open-source and privacy-focused email service.
Campaign Cleaner - The Ultimate Tool for Optimized, High-Performance Email Campaigns.
Self-Hosted Services
iRedMail - Easy to install open source mail server solution.
Mail-in-a-box - Lets you become your own mail service provider in a few easy steps.
Mailcow - The mailserver suite with the 'moo'. An easy to use dockerized selfhosted email solution.
Mailtrain - Self Hosted Newsletter App Built on Top of Nodemailer.
Mautic - Mautic Marketing Automation. Build smarter campaigns – and build them faster – with marketing automation that’s quick to learn, simple to use, and easy to iterate.
Modoboa - A solution to quickly deploy and manage a complete email server, compatible with latest standards and optimized for delivery and reputation protection.
Poste.io - Complete mailserver built in one docker container.
Sendtest.email - Test your HTML email, ⚡4email, or text version before sending. Privacy-focused, no sign-up required!
Mailsnag - Test email server for all of your SMTP needs - simulate delay and errors, preview and share emails, and more - all without sending emails to actual customers.
Email Spam Tester - Free tool to check to see if your email will end up in the spam folder.
Mastering HTML Email - This series of tutorials will take you through the fundamentals, exploring development techniques, workflow and design approaches.