Content best practices for optimal deliverability

Content is key. You’ve already read our perspective on relevance, but here are a few additional tips to optimizing your deliverability when it comes to content:

Avoid too large of an HTML file. Stay under 100KB, but try to stay between 60 and 80KB to prevent slow delivery.
Use alt tags to your advantage. Alt tags live within the image code of the HTML and display text if the image isn’t visible or loading. Rather than having a simple description like “product shot,” you might want to say something more compelling like, “Buy now and get 30% off.”
Avoid too many images. Most ISPs now block images by default. You want to have a way to capture your audience without the images enabled so they then enable them.