How to Write HTML Emails That Work Across All Clients?

Key Considerations for Writing HTML Emails When designing emails for clients like Gmail and Outlook, it's essential to understand the unique considerations that differ from web development. This guide highlights the key aspects to keep in mind:

Inline CSS vs. Tags

Unlike web development, stylesheets ( tags) are not universally supported in email clients. Thus, it's crucial to inline all CSS properties into the HTML code for compatibility.

CSS Support

Email clients have varying levels of CSS support. Some common CSS properties that may not render consistently include rounded corners, box shadows, and hover effects. Check online resources for CSS support guides and "Will it Work?" tools to verify compatibility before using specific CSS rules.

Responsive Design

Responsive design is becoming increasingly important for emails. However, traditional media query techniques may not work in all email clients. Consider using alternative approaches like fluid layouts or layout blocks that adjust dynamically.

Background Images

Background images are supported in most email clients but require VML (Vector Markup Language) compatibility for Outlook. Use VML tools provided by service providers like Campaign Monitor to create cross-client compatibility for background images.

Troubleshooting

Colspans and Rowspans: HTML email clients may handle colspans and rowspans differently, so testing across clients is essential.

Conditional CSS: Outlook supports conditional CSS that can be used to target specific email clients and apply styles accordingly.

Blue Hyperlinks: Some email clients ban blue hyperlinks. Consider using different colors or adding background colors to ensure visibility.

Webfonts: Webfonts may not always render in email clients. Check online resources for compatible webfonts and test thoroughly before implementing.

Resources

For further guidance, refer to the following resources:

Campaign Monitor Mailchimp Sitepoint Email on Acid HTML Email Boilerplate