How MailChimp Tracks Open Rates Might Surprise You


MailChimp is one of my favorite tools on the planet, while I was a long-time fan of iContact and then Constant Contact, MailChimp has without a doubt won me over. Now I’m no expert but I am learning more and more about MailChimp and its inner-workings and today came-across a pretty interesting little nugget.

So one of the mail reasons that you use a tool like MailChimp is to better understand how many people are opening your emails, clicking on links, etc. This also means that when you see the open rate that MailChimp displays you logically conclude, “that’s my open rate.” Sorry, you’re wrong, that’s not really your open rate.


Did I just blow your mind? Okay…so let me explain. MailChimp tracks opens using a small image they embed into your emails. This image only gets activated if someone hits “Display Images” – if this doesn’t happen then MailChimp doesn’t count it as an open.

What this means is that the open rate displayed by MailChimp is really just the number of people who open your email and decide to click the “Display Images” button. Sounds confusing…it sure is. Of course since so many people use MailChimp you can still use these open rates for comparison, just know that there’s a good chance your open rate is a lot higher than you thought. Also, if you think one guy (or gal) is never opening your emails, they might be, they’re just not displaying images so MailChimp has no way to know.

Now I’m not discouraging the use of MailChimp, I still love it just as much as I did yesterday. That being said, this is good to know and will change the way I look at my open rates forever.


{ 24 comments… add one }

  • Michael Rader November 15, 2013, 5:32 pm

    Yes, I guess I am confused.

    You say first that the Open Rate is, “…people who open your email and decide NOT to click the โ€œDisplay Imagesโ€ button.”

    So I gather from this that the open rate is for people who open your email but do not display the images.

    I thought the Open Rate was the opposite. People who open AND click the display images.

    • Morgan November 15, 2013, 6:53 pm

      @Michael – sorry, need to rephrase this, you are correct, open rate is people who open your email and click on display images. Updating in my post now!

  • Joe November 15, 2013, 5:55 pm

    Thanks for your post and your answer in it, I already know but have a fresh system email marketing etc. different from what you already write, `proves is best coming from your recommendation.

  • owen frager November 15, 2013, 6:48 pm

    Many people read email without opening it via the preview pane in the browser. That’s why it’s better to put text up top and a compelling message in the first 150 characters that gets their attention to want to open in full. If the image is blank and needs to be displayed- no one is going to go to that trouble given the load of other emails in queue it competes with.

    • Morgan November 15, 2013, 11:03 pm

      @Owen – excellent points! Anyone reading this should take note, some really solid advice there.

  • Mike November 16, 2013, 1:40 am

    AFAIK this is the only way to track email opens and everybody is doing it in a similar way.

  • Bryan May 15, 2014, 3:32 pm

    You’re wrong. Many people never need to click on that button, because by default their mail client DOES load images. So really the open rate is all those people PLUS people who do click the button.

  • Colleen June 2, 2014, 12:32 am

    Hi Morgan
    Thanks for the tip – I came across it while I was searching for information on another question I have:
    Would you by any chance know why a couple of my email addresses are showing large open rates (like 26 and 33!) when they haven’t clicked on any of the links inside the mail so evidently aren’t that interested in the content of the mailer?
    I’ve tried looking on mailchimp to get an answer but don’t see anything related.

    • Morgan June 2, 2014, 3:37 pm

      Thanks @Colleen, really glad this helped!

    • Danielle November 7, 2017, 7:45 pm

      Hi there, I see this link is old but I’m new to Mailchimp and discovering its limitations first hand. We are seeing massive open rates from many of our customers and making big decisions based in this, only to discover how unreliable it possibly is. I thought that perhaps in the 2+ years since you were talking about this mailChimp might have improved this glitch. Any ideas? Thanks, D

  • Tine November 18, 2014, 5:04 am

    I have the same question as Colleen. For instance, a colleague of mine is sure she didn’t open the newsletter more than once, still Mailchimp gives her ‘6 opens’. Could it be that when it’s the first e-mail in the preview pane, the image is loaded as well, so on the other hand some people who show as ‘opens’, didn’t read the newsletter at all?

  • Joe November 18, 2014, 4:37 pm

    I like you, who is the best at present to give yourself a very good description of their characteristics.

  • Michaela March 31, 2015, 12:04 pm

    Hey guys,

    another problem, or maybe question, is that mailchimp says a given person opened the newsletter for 4 times. I asked the person if she did this and she said she only opened once and doesn’t forwarded to anyone. How is that possible?

    I know that if you forward the newsletter to someone, or maybe a list, it counts on person who forwarded.

    • Morgan April 1, 2015, 8:12 am

      @Michaela – this can happen because of browser plugins/extensions that might look like opens to MailChimp but aren’t in reality. I have one friend that registers 50+ opens every time he opens any of our MailChimp emails but he’s just opening it once. Unfortunately this means you really can’t use open data to do much more than tell if someone has opened it at all.

  • Josh May 7, 2015, 2:22 am

    So helpfull…
    BOOM, give be back 2 minutes of my life… One more for writing the comment.

    • Cathy Allington May 10, 2015, 7:06 pm

      Thank you very much Morgan – yes!! Above and beyond the call of duty – much appreciated ๐Ÿ™‚

  • Cathy Allington May 7, 2015, 8:32 pm

    Greta point – but missing a very important caveat. If your subscriber views an email in the Reading Pane in Outlook but doesn’t actually open it, then Mail Chimp does not record this as an “Open”. For B2B businesses, this is a big limitation as Outlook is still the dominant email client for business. Just something to be aware of

  • alexia fotoudis March 2, 2017, 1:16 am

    thank you! I felt like my link clicks and my opens were very low, now I know why

  • Beverly July 12, 2019, 5:35 pm

    Can you please explain why, a person is reported to have opened my recent email 742 times? Did he forward it? All of the rest in that mailing report have 1-4 opens. Many thanks!


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