What is a conversion?
The moment a visitor takes the action you want: a purchase, sign-up, enquiry or download.
More details
Conversion is the end goal of most marketing activity. The conversion rate (CVR) is the percentage of visitors who convert. Conversion rate optimisation (CRO) is the systematic improvement of pages so that more visitors convert, without extra budget.
For example…
Booking.com runs well over a thousand concurrent experiments at any given moment, an estimated 25,000 tests a year. The defining principle is cultural, not technical: anyone in the company can test anything, without permission from management. When the design director wanted to test a completely new homepage in December 2017, just before peak season, it simply went ahead, even though the CEO at the time was sceptical and the head of experimentation bet a bottle of champagne that the test would flop.
Source: hbr.orgWhere it goes wrong
Conversion rates are often compared without taking the traffic source into account. Traffic from your brand name naturally converts better than traffic from a display campaign. That says nothing about the quality of the campaign, only about where someone was in their search.
Second: a rising conversion rate is not always good news. If your reach shrinks to only the people who were going to buy anyway, the percentage goes up while your numbers go down. So always look at the absolute number of conversions alongside it.
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