5 Ways to Optimize HTML for Email DeliverabilityOctober 20, 2010 By Heather Fletcher
"Most spam filters include design-based rules," he says. "If you aren't following best practices for HTML design and rendering, your messages could look like spam to the ISPs and, therefore, be delivered to your recipients' junk folders or be blocked altogether.
"Even if your message makes it to the inbox, if it doesn't render correctly or if images or links are broken, your message might be deleted; or, worse yet, be reported as spam," he concludes.
To ensure that HTML emails are received intact and render the way they should in all possible email clients, Kramer advises companies have their Web designers follow these guidelines and best practices:
- Use both HTML text and images in messages vs. just images, so that recipients can still get the gist of the message if images are turned off;
- Design images in .gif or .jpg formats and include height and width parameters so the sizing remains appropriate;
- Store images on a Web server and link them to the message, instead of embedding them in the message itself;
- Use alt text for all of the images so recipients don't need to turn the images on in order to see what is missing. And be descriptive, especially when it comes to calls-to-action. Marketers may even include the offer in their alt tags so it remains visible to their recipients at all times; and
- Don't use image maps, as they are not fully supported across all email clients. It is a better practice to slice the image, using alt tags for each section, and link each part separately.