CRO (conversion rate optimisation)

CRO, or conversion rate optimisation, is the practice of improving a website so that a larger share of visitors takes the step you want. How it works, step by step.

Updated October 2, 2026

CRO, short for conversion rate optimisation, is the practice of improving a website so that a larger share of visitors does what you want them to do, such as buy, sign up or get in touch. The goal is more results from the same visitors, instead of buying more traffic.

How it works

CRO is a cycle rather than a one-off project:

  1. Measure where visitors drop out, with analytics, a heatmap or your engagement rate.
  2. Find out why, by watching or asking visitors: usability tests, surveys or first-impression tests.
  3. Change the page based on what you learned.
  4. Test whether the change helped, ideally with an A/B test.
  5. Repeat with the next biggest problem.

Why the first screen matters for CRO

A visitor who leaves in the first seconds never reaches your form or checkout. Improving the first impression raises the number of people who even get the chance to convert. It is often the cheapest place to start, because it's one screen.

CRO without much traffic

Many CRO methods, A/B tests in particular, need a lot of visitors to give clear answers. Smaller sites can still improve: ask strangers what they think of the first screen, fix the weakest point and check again. See did your redesign work? for how to compare before and after.