You’ve created a wonderful and detailed email and fire it off to your anxiously awaiting iOS subscribers when you find that the whole message does not display, but it’s cut short ending with a button that states “Download Entire Message.” Only if the customer actually takes that step will the entire email be displayed, and if you placed your Call To Action at the very end of your email you can pretty well bet your bottom dollar that this particular send is going to tank your metrics. Gmail is now chopping your iOS emails at a mere 20 KB and what can you do about it? Nothing.

The road to Google Hades is paved with good intentions

It very well may be that the assembled mass of genius which calls the Googleplex home may have thought that this is actually a good idea, but if you ask email marketers they might unanimously tell you that it’s yet another example of the road to Hades being paved with good intentions. Sure, it does make a modicum of sense to keep emails short and to the point, but the fact that Google has taken it upon itself to make the determination that anything past the 20KB mark in your email is going to be hidden from iOS customers unless they take that step to choose to view it all (and many don’t) is questionable to say the least.

Google counts just about every character towards your 20 KB limit

The 20 KB limit is even tighter than you may think, as Gmail considers that every character in the email head applies towards that count including spaces, as well as inline styles and every tag such as


, and so on. Also note that any image URL you list will have approximately 170 characters added to it since it is redirected to Google’s proxy servers. If there is any positive news to this enforced truncation it has to be that images themselves are curiously not counted in the limit. If you play your cards right, you’ll be able to cram about 200 KB worth of images before the Google Gods determine that you’ve exceeded your ration and start to chop your emails short.

You’re allowed 10 x as many image bytes as text … Why?

It’s obvious that this 20 KB download limit prior to the subscriber’s action is set so that your mobile iOS customers with low data limits won’t have too much of their accumulated throughput accounted for through emails, but then what possible reason is there to allow ten times as many bytes for images? A byte is a byte is a byte, so why doesn’t Google set their truncation algorithm so that it starts chopping off emails at 220 KB regardless of whether it is composed of images or text? That would seem to make sense but when we are all living in a Google world, ours is not to reason why, ours is to submit to their dictates or cry.

Ensure that your iOS emails are very comfortably within these limits

If you ask 100 email marketers if they want their emails displayed with a “Download Entire Message” button part of the way through their missives, it’s quite likely that 99 will say “no way,” and just one may say “look over there … a butterfly.” However, all of those email marketers have absolutely no say in the matter. Google is determining exactly how and why email messages are truncated and we all have the choice to adapt or face the prospects of our iOS campaigns failing miserably.

It’s a real shame that all we can do is to pay very close attention to the breakdown of this truncation and ensure that our emails are comfortably within the limit. That means that it’s more important than ever to frontload the Call To Action and make all prime content prominent and above the fold. That’s just good email practice and it’s a policy that all legitimate and professional email marketers already exercise. However, the jury is out on whether it’s “right” for these limits to be externally enforced.