What is Conversion rate optimization (CRO)?
Conversion rate optimization is the systematic process of increasing the percentage of users or visitors who complete a desired action, such as a purchase or signup.
Why does Conversion rate optimization (CRO) matter for marketers?
It aims to get more leads or sales without paying for more traffic. It also depends on testing discipline and enough traffic to reach valid results.
Where does Conversion rate optimization (CRO) stand today?
Wikipedia says CRO grew out of e-commerce marketers' need to improve site performance after the dot-com bubble, that testing tools became more accessible from 2004, and that Google Website Optimizer launched in 2007 and its successor Google Optimize was discontinued in September 2023. Methods include A/B and split tests, removing obstacles and improving page speed, with statistical significance used to confirm results. It notes two schools of thought: test first to find what raises rates, or understand the audience before testing.
Common use cases
- Testing page and checkout variants
- Improving landing page forms
- Reducing friction in sign-up flows
CRO shares principles with direct response marketing, which also emphasises tracking, split testing and ongoing refinement. Because the metric depends on the goal the owner chooses, and tool availability can change, as the Google Optimize shutdown shows, teams should record what they measured and why.
Google Ads’s October 2026 test of a “Save and test asset group changes” toggle, and Typeform’s AI Landing Pages with analytics “coming soon”, are examples of vendors building testing and page tools into advertising and form products.