Paperplane converts web pages to PDF documents. PDFs are rendered using Google Chrome, so the latest web standards can be used to author source documents. The API also allows you to convert multiple documents in parallel, and automatically uploads PDFs to cloud storage.
BeeFree.io - Bee is MailUp's drag-&-drop editor for responsive design emails.
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
Topol.io - Create professional Email templates easily - Drag & Drop Email Builder.
DocRaptor - As the only API powered by the Prince HTML-to-PDF engine, DocRaptor provides the best support for complex PDFs with powerful support for headers, page breaks, page numbers, flexbox, watermarks, accessible PDFs, and much more
MJML - The open source framework for responsive emails
HTMLEmail.io - Responsive HTML email templates for startups & developers