Way to Check Email File Size

James Matney

I am interested in a way to check the file size of my Act-on Emails. I know that Gmail cuts off emails with a file size of 140-ish kb. But I have also seen suggestions of keeping an email nearer the 40-60kb range.

I know that Litmus has a way to check the file size, but we stopped using Litmus some time back.

Is there a way to check the file size within Act-on? The process I came up with is to use the "Download Creatives" option, and then just see how big the HTML file is. The only thing I can think of where this may misrepresent the size of the file is that this probably includes markup of dynamic content, which means it is showing more markup in the file than is what is actually in the finished product when Act-on processes and sends out the email.

Have I found the best possible way to check file size in Act-on, or is the another/better way?

Thank you.




  • Comment author
    Brian Hertzberg
    • Official comment

    Hi James,

    Using the Download Creatives option in the Message Composer is definitely a good way to see how large the HTML file for your message will be, but you make a good point regarding markup of Dynamic Content resulting in a file size that won't accurately reflect what a contact receives in their mailbox.

    The best way to fully check would be to send some test messages that will meet your various Dynamic Content criteria, and then download the delivered messages and checking the file size on those.

  • Comment author
    James Matney

    Thanks for the reply. I gave it a try by sending the email to an Outlook account. When I save the email as an HTML and then check the properties, it shows as almost 500 kb. This is a bit larger than the 100 kb download of the "Creatives". It is purely an HTML file that I am checking the size, so it shouldn't include any graphics. Does Outlook add a bunch of markup? Is there a best agent to send the email that I can save it and get a more accurate file size? I appreciate any suggestions.


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