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What is Conversion Rate Optimization? Definitions, Tools and Examples
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What is Conversion Rate Optimization? Definitions, Tools and Examples

Conversion Rate Optimization (CRO)

Conversion Rate Optimization (or CRO) is the process by which marketers increase the proportion of a website’s visitors who become customers. The highest performing companies are twice as likely (52%) to have a CRO strategy than those with low conversion rates.

CRO follows an iterative pattern, also described as a “Test and Learn” approach. Marketers make small adjustments to a website and track the resulting changes in performance. In this article we explore the uses, strategies and best-practices associated with Conversion Rate Optimization.

Conversion Rate Optimization has become a standard practice within digital marketing. By conducting customer research and hypothesis testing, eCommerce businesses can optimize their conversion funnels and increase their revenues (see our 5-step CRO Strategy below). The high return-on-investment provided by CRO marketing campaigns has led some experts, like Peep Laja from ConversionXL or André Morys from ConversionKraft, to describe CRO as Conversion Revenue Optimization. 

The famous SEO software provider – MOZ – defines CRO in terms of consumer behaviour:

Conversion rate optimization (CRO) is the systematic process of increasing the percentage of website visitors who take a desired action — be that filling out a form, becoming customers, or otherwise. The CRO process involves understanding how users move through your site, what actions they take, and what’s stopping them from completing your goals.

Online advertising experts like WordStream apply the same terms to promotional campaigns:

Conversion rate optimization (CRO) is the process of optimizing your sponsored search ads, landing pages, and overall website design to raise your conversion rate. In other words, the goal is for the highest possible percentage of visitors to your site to convert, or complete your desired action. CRO is quickly gaining in popularity because it’s seen as a way to increase profits from sales without raising your advertising spend.

Whatever the context, Conversion rate optimization is about optimizing your Costs versus your Revenues. It is about being able to increase your online profits without increasing your marketing budget.

The internet is the world’s largest and most accessible market. Millions of users browse for deals on a minute-by-minute basis. This is all well and good, but eCommerce businesses rely on something more complicated taking place – those visitors transforming into customers. Conversion Rate Optimization is important because it helps you to reduce your customer acquisition costs. Rather than generating more traffic with expensive promotional campaigns (such as PPC, Facebook Ads or Native Advertising,) it allows you to enhance the value of the visitors you already have.

Most marketing teams are (still) focused on driving traffic to their websites in the “hope” that it will convert into sales. The strategy is simply to push more visitors into the funnel. In a market where traffic is an unlimited resource, cheap and uncompetitive, it is easy (and somewhat logical) to concentrate on acquisition. But which market can be described like this in 2018? Not the USA, where competition is strong in any given industry, and certainly not in Europe.

Think about a country like Sweden, for example, with a population shy of 10 million people: to succeed in this comparatively small market, online businesses need to be more persuasive. Instead of becoming more visible, they need to provide better valuecustomer experience and communication. As such, it’s not surprising that the majority of world renowned experts in conversion optimization and neuromarketing are from countries like Latvia (Peep Laja), the Netherlands (Bart Schutz, Ton Wesseling) or Sweden (John Ekman).

Of course, population size is not the only reason that businesses focus on conversions…

When Amazon launched in 1995, online competition was non-existent. One might think that CRO did not need to be prioritised. However, Amazon was one of the first online businesses to develop and promote CRO internally. Over the years, Amazon has become THE reference when it comes to Conversion Rate Optimization.

In a global environment where cost-per-click on Adwords and Native Ads networks is always increasing, where online competition is ever faster and more aggressive, it is increasingly important for online businesses to get as many sales as possible from their traffic.

This section outlines the 5 steps that make up every successful conversion rate optimization (CRO) strategy. 

A thorough conversion rate optimization strategy includes research, testing and analysis, and involves every aspect of your product. For example, User Experience (UX) is fundamental to effective CRO. Enhancing customer experience makes it more likely that a visitor will return to your website. Return visitors are much more likely to become clients.

It is important to note that a conversion rate optimization strategy does not only help to increase the number of visitors who convert into customers; it also contributes to their value and retention.

CRO strategies vary between optimization agencies. Some focus exclusively on Analytics data, others on User Testing or Consumer Behavior. Here is the method we use at Convertize, combining each of these approaches:

5 steps to a successful Conversion Rate Optimization (CRO) strategy

  1. Data Analysis
  2. Hypothesis creation
  3. Design & Development
  4. Integration and A/B Testing
  5. Learning and Improvements

A well-considered CRO strategy will allow your organisation to increase its market share, revenue and efficiency. It is essential that your methods reflect your business context. The first stage in any CRO campaign is to reaffirm your value proposition and your goals. 

The first stage of data analysis is identifying which information is valuable and which is not. This means drilling down into the data from CRM systems, website analytics and eCommerce purchasing histories.

What follows is a mixture of qualitative and quantitative methods. The qualitative approach involves analysing customer feedback and user research. Such data is usually produced through surveys, user testing and heat mapping. These qualitative insights can then be compared to the trends described in your quantitative data. You need to analyse your web analytics and funnel data to see where visitors enter and leave the conversion process.

Together, qualitative and quantitative methods reveal what motivates your users and what shapes their browsing behaviour. 

Once you have compiled your data and analysed the trends, you will be in a position to create a hypothesis. This is simply the effect that you think you can achieve with a change to your website. Your hypothesis is the prediction that you mean to test.

For example, you might hypothesise that changing X (the number of product on your homepage) to Y (a smaller number of product) will produce Z (more clicks, in total, on the products displayed). This will allow you to test for ways to produce different outcomes on a consistent basis. It will also allow you to suggest possible reasons for visitors not taking the actions you wanted them to.

Using Web Psychology and Consumer Behaviour is the best way to leverage Analytics data

Understanding the mindset of potential customers is an important part of optimising your website. This means studying the thoughts, assumptions and habits which influence a person’s actions. Whenever you create variants in A/B testing, you should consider this customer profile and the cognitive biases that may shape their behaviour.

We like to think of ourselves as being rational and objective when making decisions. In fact, this is very rarely the case. We are predisposed to certain perceptual biases that skew our judgement and inform our decisions. Cognitive biases assume many forms, such as the bandwagon effect (essentially following the crowd) or selective perception (where expectations influence how a person perceives reality). A thorough understanding of consumer psychology is indispensable for anyone optimising their conversion funnel. 


With your hypothesis in hand, you will be able to design your AB testing experiments. These AB tests will determine how to ensure more of your visitors convert into customers.

You should target a range of factors that prevent browsers from committing to a purchase: confusion, lack of trust, frustration or indecision.

Your solutions will be suggested by the outcome of your tests. The results will illustrate how small changes, such as adding trust messages or nurturing credibility, enhance your conversion rate.

This works by testing a ‘variant’ or ‘variants’ against a ‘control’. If your ‘control’ is A – your existing or current page – then B is the newly developed alternative or ‘variant’.

The testing platform allows you to run simultaneous tests until you determine which version of a page is your winner. The test will randomly assign traffic (usually 50:50) to each page, and the page that garners the highest conversion rate is the winner.

If your A/B test fails

This will mean examining the data, working out which aspects failed, and determining why. Parts of your test may have been successful, even if others were not. There is also the possibility of a bug or an issue with the execution. If a ‘control’ is proven to be the best method, you need to return to the drawing board and create a new hypothesis.

If the A/B test wins

Once a variant page has been declared the winner … you still need to examine the data. This will allow you to determine two important things:

  • Whether the test was statistically significant
  • Why a variant worked better than the ‘control’

When these to questions have been answered, you will be able to optimise your website by making the necessary changes. By setting the winning variant to be shown to 100% of your website’s traffic (within the CRO testing tool) you will be able to enjoy this new win straightaway.

How to use this 5-step CRO methodology

Implementing a clear and simple conversion rate optimization strategy will allow you and your company to keep up-to-date with your audience’s needs and improve their user experience. By removing unclear sections and simplifying navigation and use, you will often enhance the consumer’s journey and increase the likelihood of them converting into customers.

Choosing a CRO Agency to optimize your website is one of the most important marketing decisions an eCommerce business can make. Identifying a CRO expert who will prioritise your goals and apply a rigorous method is essential, but how do you find the right agency?

Asking the right questions to your Conversion Rate Optimization Agency is key. Here are some things to consider when interviewing a consultant:

  • Do they have a clearly defined methodology? Strategic thinking is the only way to perform CRO efficiently.
  • What analytical techniques do they use? A mixture of qualitative and quantitative analysis can form a picture of how visitors experience your site.
  • Will they understand my business? Any optimization campaign should complement your business’s fundamental value proposition. 

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In this section, we explain how CRO actually works and name the tools you need to conduct it.  

A/B testing Solutions

An iterative process of adjustment and measurement, allowing you to track the effect of small changes to your website. When CRO is mentioned, A/B Testing is the next term that comes to mind. It is a standard tool for validating changes during the optimization process. The most popular tools for A/B testing are outlined in a dedicated post. However, the most popular platforms are:

Customer journey analysis

This involves analysing all aspects of a customer’s interaction with your company. Behavioural data is compared with information about customer satisfaction and loyalty to show where waste or dissatisfaction occurs during the customer journey. The practice is particularly useful for identifying “pain points” experienced by customers. Some of the most popular tools include:

Online surveys/customer feedback

When establishing a customer profile, responses to surveys are a valuable tool. It is easy to develop assumptions about how your customers feel and what they want from you. These assumptions can be dangerous. Asking your customers for feedback directly allows you to challenge this guesswork and there is a good range of free platforms for creating customer surveys: 


Understanding your customers is essential to any optimization programme. Once you have established segmented customer profiles, based on behaviour, communication and customer success can be enhanced more easily. Some of the most popular tools include:

Copy optimisation

Copywriting is perhaps the single most important aspect of web marketing. Despite this, it is rarely afforded the same time and effort as other optimization activities. Copy can be optimized to provide persuasive communication, and to make content more visible to search engines (SEO). Whilst there is no way to produce good copy automatically, there are tools available to help with SEO research and Copy Optimization:


Using mouse-tracking information, heatmapping provides a visual map of a visitor’s journey through your site. Popular tools include:

Cart abandonment analysis

Cart abandonment is an inevitable part of eCommerce. In recent years, automatic re-marketing and re-targeting strategies have been developed, which promise to recover up to 63% of abandoned visits. The easiest way to gain quantitative data on cart abandonment is with Google Analytics or Mixpanel. For qualitative insights, platforms like Qualaroo provide automatic cart abandonment notifications. In order to replay real page visits and analyse customer interactions, a number of tools can be installed on your website:

Our library of expert insights on Conversion Rate Optimization is freely available to browse. They provide an archive of tips and best-practice guidelines relating to Conversion Rate Optimization. To help you browse our pages, here is a summary of our articles and who might use them:

1. Starting Out with Conversion Rate Optimization: Beginner’s Guides

2. Looking for Optimization Tactics to Improve Your Conversion Rates

You have already defined your conversion rate optimization strategy and are looking for practical information and tactics to help you create your hypothesis. Here are a few articles you may want to read:

3. Looking for Conversion Rate Optimization Success Stories

You can also read conversion tactics and funnel analysis about Amazon Prime, BlaBlaCarLidlNET-A-PORTER, et John Lewis, and more