What’s the ideal HTML-to-text ratio?

The ideal HTML to text ratio is not precisely defined but should include substantial text content rather than relying primarily on images. Messages that are mostly images with minimal text trigger spam filters suspicious of image based spam.

Best practice suggests at least 60% text to 40% images, though this varies by content type. Product showcases naturally use more images; newsletters typically have more text. The key is including enough text for filters to analyze.

Beyond filter considerations, text heavy emails are more accessible, load faster, and work when images are blocked. Balance visual appeal with functional text content that conveys your message even without images.