What Is Email Development? A Beginner’s Guide

If you’ve ever opened a beautifully designed newsletter or a promotional email with clear calls-to-action, you’ve seen the work of an email developer.

While web developers build websites and apps, email developers specialize in coding and designing emails that look great across dozens of email clients (like Gmail, Outlook, and Apple Mail) and devices. It’s a unique niche in the tech world, part design, part coding, and part problem-solving.

But what exactly does email development mean, and why is it so important in 2025? Let’s break it down.

Email Development in Simple Terms

At its core, email development is the process of building HTML and CSS templates for marketing campaigns, newsletters, transactional messages, and automated workflows.

Unlike a standard web page, emails face strict limitations:

• Not all CSS works across clients.
• JavaScript is usually not allowed.
• Many designs must rely on old-school coding methods (like tables) to render consistently.
• That means email developers have to be both creative and resourceful to make sure designs display correctly everywhere.

The Building Blocks of Email Development

Just like websites, emails are built with:

• HTML → the structure (headings, text, images, buttons).
• CSS → the style (colors, fonts, spacing).
• Fallbacks → backups for when certain features don’t work in Outlook or Gmail.
• On top of that, email developers often work with:

Templates & frameworks (like MJML or modular design systems).

Testing tools to preview emails across 50+ clients and devices.

ESP integrations (Mailchimp, Klaviyo, HubSpot, etc.) to make designs functional and personalized.