What is the optimum for image loading


I am new to email marketing.
I have received some feedback that the images are loading very slowly - more than 20 secs. In my own tests in different user environments, the test results can be from 1 - 7 secs.

I know file sizes are kept to 100Kb or below when possible, which has been done.

Is there an industry standard for image loading?
What factors affect image loading?

I am not sure what's the cause for the image loading but I could help to minimise complaints if I can quote an industry standard.

Thanks for your help.

Dave Dave, 9 years ago

Images in email are downloaded just like images in a web page (unless you actual embed the images in an email, in which case the email itself takes longer to download but the images appear immediately once downloaded). The only real bottleneck should be the recipients web connection.

Stig Stig, 9 years ago

Hi, and welcome :)

File size and load time is important to be aware of, both with email and web. A total size of 100kb is not a lot for a newsletter, but with a dial up line, everything takes time.. Especially if you're using many small files. You can always spend a little extra time choosing the right format and compression for each graphic.

A cool thing about HTML email , though, is that you don't necessarily need too many images to make a good design. You can get far by just making a good layout with CSS in a good color scheme, and using images to support the design (tiled backgrounds, pictures, button background image for your call-to-action..).

But a 100kb limit is a good starting point. The Email Design Gallery is always a good resource to see what others are doing.


The Campaign Monitor Blog – HTML email smarts to go with your good looks.
emaildummy, 9 years ago

Thanks for both replies.

All images are not embeded, they are referenced from an image server as recommended by industry standards. We had feedback that sometimes clicking on the "click here if you can't see this email" tends to be faster than loading in the images.
Could it be a email client issue?

I did ask about what the computer operating system and internet access from those who complained. I am tongue tied when they are using like a newly bought computer with windows vista and fast broadband access.

If we take image loading in email the same as for web pages, then do you think max 10 secs is the max limit before the mail is deleted or un-subscribed?

Appreciate your comments!

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