What performs best? A pop-up that's personalized by region, or a simpler pop-up that only asks for an email address? Take your best guess on the personalized pop-up test and see if you win.

To increase opens and clicks, should your subject line copy be specific or emphasize benefit? Take your best guess on this email subject line A/B test to find out. Then, apply the findings to optimize your own email marketing success.

When getting users to complete your sign-up form, does copy really matter? Take your best guess on this sleek sign in test to find out.

Is it better to include or remove a sign-up overlay to increase conversions? Take your best guess on this smart sign-up test to find out.

What's the optimal placement of video on product pages? In the product display thumbnails or just on their own? Take your best guess on this video marketing A/B to find out. Then, apply the findings to optimize your own video marketing success.

Take your best guess on this eCommerce A/B test to find out if it was better to include the price symbol, or leave it out. Then, apply the findings to optimize your own eCommerce conversions.

Take your best guess on this eCommerce A/B test to find out if it was better to include or remove the dollar sign to donation contributions. Then apply the findings to optimize your own eCommerce or donation site.

Did the version with or without the pre-selected amount win? Take your best guess, see if you win, and apply the findings to optimize your own site.

Did the bottom notification bar or exit pop-up increase Clickthrough Rate (CTR) conversions? Take your best guess, see if you win, and apply the findings.