CRM, Direct marketing

Email Design 2017 - #5 Email File Sizes: why do they matter?

Email file size. It may not sound like the most exciting of topics, but trust us, it’s incredibly important if you want to create effective emails that resonate with your subscribers.

First of all, email sizes need to be considered in two distinct parts: code and images. The code should be under 102kb because unfortunately, Gmail clips the email if the HTML code is over 102kb. This means it will be displayed up until a point and then cut off. Not ideal.

To speed up load time, it’s a good idea to keep image sizes to a minimum. Each image you load is a request to the server, so the more images and the larger they are, the longer an email will take to load. This is particularly important to bear in mind for mobile users as large images will eat up their data like there’s no tomorrow.

Wherever possible, emails should be kept to under 500kb in size. To minimize the size, keep your code as lean as possible, and compress all images and GIFs using both lossy and lossless compression.

Email size will increase considerably if you use GIFs, with the increase depending on the amount of frames and colours. With this in mind, we recommend against using multiple GIFs in an email. As well as looking messy and distracting, it will really increase the file size.

When it comes to using video in an email: just don’t do it! As well as dramatically ramping up the file size, HTML 5 video is only supported on iOS mail and – meaning it won’t play in most email clients. For more widely supported movement in email, you could use a GIF, cinemagraph or an animated play button.

Want to learn more? Just get in touch with Ian Reeves. We’ll happily help you with all things email related.