MailChimp's researchers are constantly analyzing data to help you make the most of your email campaigns. Check back often—we're always learning something new.


Comprehensive deep-dives into the aspects of email marketing most important to you


Average open rate for emails sent by users in the hobbies industry, the highest we’ve found


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The latest findings from our data scientists


Average open rate for emails sent by companies with 1 to 10 employees


Effect of content to link ratio on click rate

Be careful to balance your links with good content. One sentence (that’s around 7 to 10 words) per link seems to be the sweet spot for maximum engagement.

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40 million

Number of emails sent through MailChimp we analyzed to answer the question, “How should I write my subject lines so that more recipients will open my emails?”


Effect of purchased list correlation on spam complaint rate

The more a list correlates with lists available for purchase online, the higher its spam complaint rate. In other words, a purchased list is a dead list.

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Increase in click rate that a list's segmented campaigns see over its non-segmented campaigns


Email address e-commerce value by domain

Hotmail AOL Yahoo Gmail
AOL 0.70%
Yahoo 6.40% 6.20%
Gmail 3.70% 4.90% 1.80%
Comcast 7.30% 7.50% -0.40% 0.40%

Hotmail addresses spend 0.70% more than AOL addresses, while AOL addresses spend 6.20% more than Yahoo.

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Number of split tests sent in 2013 using MailChimp’s A/B testing feature


Email opens by time of day

Following the pattern of an average workday, emails are opened between 9am and 12pm, with 1pm to 5pm coming in just behind. After 9pm, open rates make a steep decline.

Learn more about send-time optimization


Distinct words in the 24 billion delivered emails we analyzed in our study of subject line efficacy, including “freebie,” “cancelled,” and “fundraiser”



Increase in unsubscribes on Cyber Monday 2012, compared to the previous Monday


Effects of subscriber recency on open and click rates

Your newest subscribers are your best subscribers. They’re most engaged immediately after signup, but usually trail off over time.

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