Conversion rate optimisation

What it means

CRO, conversion rate optimisation, is systematically improving a website so that a larger share of visitors take the desired action, such as buying, filling in a form or making a booking. The aim is to get more results from existing traffic without spending more on advertising.

The core metric is the conversion rate, the share of visitors who convert. If a shop with 10,000 visits a month lifts it from 1 to 1.5 percent, it gets half as many orders again, which would otherwise require a considerably larger advertising budget.

CRO relies on data and hypotheses rather than impressions. Web analytics shows where people drop off, heatmaps and session recordings reveal what gets in their way, and changes are validated with A/B tests so it is clear whether an improvement came from the change or from chance.

How it works in practice

Typical changes remove friction: a shorter form, a clear call to action, a visible price including delivery, faster loading and trust signals such as reviews and contact details. On mobile, a bigger button and fewer pop-ups often help on their own.

It pays to start where most people arrive and most leave, such as the main campaign landing page or the basket. A small improvement on a high-traffic page brings more than a perfect redesign of a page that hardly anyone visits.

Qualitative insight comes from usability testing with five to eight people who complete tasks while thinking aloud. It often uncovers problems hidden in the numbers, such as an unclear service name or a form field people do not understand.

What to watch out for

An A/B test on a small site needs a long time to produce a statistically reliable result. Stopping a test after two days because one version is ahead often leads to rolling out a change that improved nothing. With low traffic, bigger changes and qualitative research work better.

Conversion is not the only value. Aggressive pop-ups, fake urgency or hidden pre-ticked options can lift numbers briefly but damage trust and may amount to an unfair commercial practice. In the long run it pays to improve the site for people, not against them.