What is the best way to create an email from existing HTML content?

The option that is best for creating an email from existing HTML content is HTML paste. This method allows users to directly input their pre-written HTML code into the Salesforce Marketing Cloud email editor. It is particularly beneficial for those who have custom-designed emails or specific formatting requirements, as it preserves the existing HTML structure and styling without the need for alteration or reformatting.

When using the HTML paste approach, users can ensure that their email layout, images, and inline styles are accurately represented, enabling a more accurate preview of how the email will appear to recipients. This option is advantageous for those familiar with HTML and seeking precise control over their email designs.

In contrast, the other options, such as empty template, themed template, and text-only, do not assist in inputting existing HTML content as efficiently. An empty template requires starting from scratch, a themed template offers a pre-designed layout that may not align with existing HTML, and the text-only option strips away any HTML formatting, resulting in a plain text email. Therefore, HTML paste is the most suitable option for users looking to utilize their existing HTML content effectively.