Automatic image enablement was introduced shortly after image caching. While Gmail previously blocked images by default, it now automatically displays images (this is, of course, after they’ve been cached and checked for viruses).

Before: Images off by default

Now: Images on by default

Prior to automatic image enablement, if you weren’t using images-off optimization techniques, like styled ALT text, bulletproof buttons, and background colors, then a large portion of your Gmail subscribers were likely having a poor email experience. Now Gmail users can see the hard work and effort you’ve put into your designs without having to manually enable images!

Your messages are now more safe and secure, your images are checked for known viruses or malware, and you’ll never have to press that pesky “display images below” link again.
John Rae-Grant
Product Manager, Google


What would you be upset about? This is great news for email designers! Prior to this update, 57% of Gmail users turned images on—which means that a whopping 43% of Gmail users viewed emails with images disabled!

What should you do?

Send your emails as you normally do! You’ll have a sense of relief knowing that your Gmail subscribers will, by default, see your design and associated content. However, we still suggest optimizing for images off through the use of bulletproof buttons, ALT text, background colors, and a proper balance of imagery and live text. Regardless of whether Gmail may display images by default now, many other clients do not.

Also, keep in mind that your open rates may be affected. Email tracking relies on a unique image being included in a campaign and that image being downloaded and displayed within the email. Every time the image is downloaded from the server, the tracking software marks that as an email open. Now that Gmail uses automatic image downloads, these unique “open tracker pixels” will be viewed more often, resulting in increased open rates.

How much should you expect your open rates to increase? The number of Gmail users on your list, combined with their preferred email client, will definitely play a factor. Overall, we’ve seen about a 341% increase in Gmail opens since the introduction of image enablement and image caching!