Conversion
A conversion is the moment when a visitor to a website or app does exactly what the operator wants — such as making a purchase, signing up, or submitting a form. The share of visitors who do this is called the conversion rate and is one of the most important metrics in online business.
Anyone who runs a website usually has a specific goal in mind. An online shop wants visitors to place an order. A newspaper wants readers to take out a subscription. An app wants users to create an account. Whenever a visitor performs exactly this desired action, it is called a conversion. The English word literally means “transformation”: a mere visitor becomes a customer, a subscriber, or a registered user. What counts as a conversion is defined by each company itself.
The metric on which advertising budgets depend
Visitor numbers alone say little. A page can attract a hundred thousand people a day and still not make any money. Only the conversion shows whether attention actually turns into a result. That’s why companies calculate the conversion rate: the share of visitors who carry out the desired action. If 10,000 people come to a shop page and 200 of them buy something, the conversion rate is two percent.
Such figures are typical. In online retail, one to three percent is considered normal, and anything above that is considered very good. That sounds low, but it is economically decisive. Doubling the rate from two to four percent doubles revenue without a single additional visitor coming to the page. This is exactly why companies invest a lot of money in improving their pages in small steps.
The metric also determines how much advertising is worth. If a company knows that a hundred clicks from an ad bring in an average of two orders, it can calculate how much a click is allowed to cost. Without this calculation, online advertising would be pure guesswork. Almost the entire business model of Google and Meta relies on advertisers being able to measure their conversions.
From click to order: the measurement
For a conversion to be counted, the website has to report it. To do this, a small piece of code is embedded on the confirmation page — for example, the “Thank you for your order” page. When a user opens this page, the code sends a signal to an analytics system such as Google Analytics. This system counts the signals and assigns them accordingly.
Attribution — that is, the question of who deserves credit for the success — is more difficult. Someone sees an ad on Instagram, searches on Google three days later, and only makes the purchase a week after that via a newsletter. Which channel caused the conversion? Different attribution models answer this differently: sometimes the first contact counts, sometimes the last, and sometimes all touchpoints are credited proportionally. The method chosen can significantly change the result.
To increase the rate, companies test variants against each other. In what is known as an A/B test, one half of visitors gets a green order button, the other half an orange one. After a few days, it becomes clear which version generated more orders. What gets tested includes texts, images, prices, and the number of form fields. A common mistake is drawing conclusions from just a few hundred visitors — with small numbers, the difference is often pure chance.
Conversion in news, shops, and AI products
In everyday life, one encounters conversions constantly without hearing the term. The eye-catching buy button, the countdown “only two items left,” the pop-up with the discount code: all of these are attempts to increase the conversion rate. The deliberately short path to checkout is also part of this, since every additional form field costs drop-offs.
In business news, the term comes up when companies explain their figures. Providers of software subscriptions often cite the rate at which free users become paying customers. For AI services like ChatGPT, this conversion from the free to the paid version is the decisive figure, because operating the models costs money with every request.
It’s important to distinguish this from similar metrics. The click-through rate only measures how many people click on an ad — it says nothing about whether anything happens afterward. The bounce rate measures the opposite of conversion: visitors who leave immediately. A high click-through rate combined with a low conversion rate is a typical warning sign. It usually means the ad promises more than the page behind it delivers.