What is Conversion Optimization?

Need to understand how to turn your website’s visitors into customers?

Need to understand how to turn your website’s visitors into customers?

Welcome to our complete guide on Conversion Rate Optimization (CRO).

This resource is meant to help you regardless of your current level of knowledge on the subject—be it to understand the concept of conversion rate optimization (CRO) or even learn skills to improve the conversions on your site, this page will definitely help you.

This guidebook was written by professionals employed by Supersonic, the first company specializing in conversion optimization in Brazil. They use the concepts presented here on a daily basis to generate millions of dollars of increase in revenue for their clients. So, you can rely on the quality of the content.

Why you should know what CRO means

Because this is possibly the strategy that will have the greatest Return on Investment (ROI) out of all your marketing efforts. So, yes, this is very important.

Hard to believe? Then listen to some of the greatest digital marketing specialists in Brazil:

Foto: Gabriel Costa - Growth Manager da Resultados Digitais
“To us at Resultados Digitais, CRO has been one of the most important strategies and practices for a long time. The most immediate effect is an increase in results while working with the same resources. Consequently, there is a reduction in CAC (Customer Acquisition Cost), a metric we watch closely at all times, which is fundamental to the well-being of our business. It is a strategy we have prioritized for over a year, and the numbers keep improving.” Gabriel Costa
Growth Manager at Resultados Digitais

Who is this guide for?

Who is this guide for?
  • Business managers.
  • Marketing department directors.
  • Digital marketing professionals.
  • Students.
  • Anyone interested in increasing a website’s conversions and profits.
Chapter 1

What is conversion optimization?

A sigla CRO (Conversion Rate Optimization - Otimização de taxa de conversão), é, em apenas uma frase: extrair o maior número possível de clientes dentre os visitantes que você tem em seu site. Não confunda com taxa de rejeição (Bounce Rate).

But before we go into the details, we need to clearly understand the concept of conversion.

What is a conversion?

A conversion is nothing more than the action you want the visitor on your website to carry out. Look at some examples:

  • For an e-commerce, the main conversion is usually a sale. So every time a user makes a purchase in an e-commerce, his action represents a conversion.
  • Em um site que gera contatos (leads) para vendedores, não é possível fazer a venda diretamente on-line. O site existe para atrair clientes potenciais e alimentar o departamento comercial da empresa com oportunidades de negócio. Nesse cenário, então, quando o usuário entra em contato com a empresa ou deixa seus dados para ser contatado, ele está realizando uma conversão.
  • On the website of a company that operates with the SaaS (Software as a Service) model, the goal is to attract new users to acquire software. Therefore, in this case, a conversion takes place when a user registers to gain access to the system.

As can you see, the precise idea of what defines a “conversion” varies from site to site once we consider the goals at stake. However, there is something in common in all of them: a conversion happens when visits turn into money.

In other words, your key conversion will always be the action the user carries out on your site, making your company profit more.

What is a conversion?
Beginners want visitors, professionals want conversions

For your business, a visit is probably nothing more than a cost. It costs to keep the site online, to advertise it, etc. So we always say that the real objective of those who know what they are doing on the internet is not to increase the number of visits, but to increase conversions. That is the only way you will turn your cost into income.

Find out how much each visit costs to your website:

How much you spend generating visits monthly?

Sponsored links, inbound marketing, SEO, etc.

How many visits do you get each month?

$ 0.00

This is the price you pay for each visitor who accesses your site.

What is conversion rate?

A website’s conversion rate is the percentage of visitors who carry out a conversion.

How do you calculate your conversion rate? This is the simplest way:

  • In your Google Analytics, find the number of visits on your website over a specific period of time. For instance, in the last 30 days.
  • Gather how many conversions (sales, interested contacts, etc.) your site generated during the same period.
  • Calculate the conversion rate with the following formula:
    Formula: Conversion rate = 100 x number of conversions / amount of visits

Want us to calculate it for you? No problem!

Just use our conversion rate calculator:

How many conversions did you have during the period you want to review?

How many visits did you have during the same period of time?


This is your site’s conversion rate

What is conversion optimization?

(Agora que você entendeu o que é conversão e o que é taxa de conversão, ficou fácil, certo?)

Conversion Optimization—or Conversion Rate Optimization (CRO)—consists of an organized effort to increase the conversion rate of a website.

O interesse em otimização de conversões ganhou muita força em todo o mundo desde o início da segunda década deste século, conforme nos mostra o Google Trends:

Gráfico: Interesse com o passar do tempo

Today, CRO is seen as an essential practice for any business that wants to have high-level results on its website or in any other digital channel.

And it all makes sense, since the task of optimizing conversion rates helps improve strategic business metrics such as:

  • Revenue growth grate.
  • Profit margin.
  • Acquisition cost.
  • Customer lifetime value.nte).
  • Average ticket (how much a customer spends, on average, on each purchase from you).cada compra com você).
  • Subscription renewal rate.
  • Rate of visitors who upgrade.
  • … and many others.

Some of the most successful companies nowadays have one thing in common: they’ve invested heavily in conversion optimization for a long time. Amazon, Airbnb, Booking, Google, eBay… They all take CRO very seriously and reap the benefits of this daily.

What conversion optimization is NOT

Unfortunately, once businesses and professionals see the existing potential in conversion optimization, many of them end up falling for common “traps”.

It’s normal for these mistakes to occur. After all, our human nature leads us to always want quick and easy results.

To avoid suffering from this too, learn now what others had to learn through their mistakes.

The three biggest mistakes made by those who are starting to practice CRO:

Conversion optimization is not …
… copying others.

Do not assume that a change that apparently increased the conversion rate of a random website will also increase your results.

Cada site possui um público-alvo específico, com necessidades e inseguranças específicas.

So, copying what your competitor does is dangerous. In fact, it is very likely he does not know what he is doing.

Conversion optimization is not …
… making changes without running tests.

As you will see throughout this guidebook, every change made in deliberate conversion optimization strategies is scientifically tested—through A/B or multivariate testing—in order to statistically validate that it actually improves the conversions on your site.

We are tired of seeing people make harmful changes to their sites believing they will bring improvements. Big mistake.

Today, with the testing resources to which we have access, it doesn’t make sense to run the risk of publishing a change without knowing the real impact it will bring to your business.

Conversion optimization is not …
… making decisions based on opinions.

In high-level digital marketing, there is no room for personal opinions without justification.

Decisions about what to do on a website and how to do it should not be made based on mere opinions and guesses. They should be based on reliable research and analysis. Like we always say: o not bring your opinion to a data contest.

Companies that take this to heart (known as data-driven) not only make more money, but also suffer less from personal conflicts among employees who have differing opinions.

Chapter 2

Why work on conversion optimization?

Icone: Todos os seus canais de marketing se beneficiam com CRO

All your marketing channels benefit from CRO

All your advertising efforts on the internet probably lead visits to your website or to your landing pages, right?

All your marketing channels benefit from CRO

Have you ever stopped to think that if you double the conversion rate on your site, you will automatically double the conversion rate of all your efforts to generate traffic on the internet?

Consider the power this holds. With a single effort, you can double the conversions of your work in SEO, AdWords, social media, content marketing…

Additionally, when you work with Pay Per Click traffic acquisition (Google AdWords, Facebook Ads, etc.), pointing users to a website that converts better means that you can, if you wish, pay extra for your visitor’s click, leaving your competitors behind in the race for visibility while still making a profitable investment.

Icone: CRO aumenta seu faturamento sem aumentar seus custos

CRO increases revenue without increasing costs

If you want to increase your income, you usually need to also increase your costs.

If you want more salesmen, costs will increase due to hiring, salaries, and commissions. If you want more ads running, your media costs will also increase… and so forth.

However, when you increase your conversion rate, your revenue also increases (more sales), but you do not take on new fixed costs for your company. After all, all you are doing is making your website better.

Because of this unique circumstance, we have seen cases in which a particular increase in revenue actually led to a much higher, prorated increase in the profits of the companies. And profits are the ultimate goal of every company, aren’t they?

Icon: As your user experience improves, your competitors are left in the dust when it’s time to close a deal

As your user experience improves, your competitors are left in the dust when it’s time to close a deal

Websites with a high conversion rate invariably please their visitors by offering a positive experience and precise content. Even Google considers this an important factor in its ranking algorithm.

If you do CRO, who do you think your customer will choose when it’s time to close the deal? You, with an optimized website, or your competitors, with ordinary ones?

Icon: CRO reduces your Customer Acquisition Cost (CAC)

CRO reduces your Customer Acquisition Cost (CAC)

Increasing your conversion rate means getting more customers out of the same volume of traffic you already have. And this means that your Customer Acquisition Cost (CAC) lowers as your conversion rate increases—an inversely proportional relationship.

CRO reduces your Customer Acquisition Cost (CAC)

And this is fundamental. After all, often the difference between a viable business and a failing one is the CAC.

In addition, companies that are able to work with a reduced CAC can grow quickly, making competitors struggle trying to keep up.

Icon: Your partners and associates will love you

Your partners and associates will love you

If you can convert more visitors into customers compared to your competitors, you will naturally be a priority choice for your commercial partners (or associates) when they need to refer a solution to one of their leads.

And no wonder. After all, the likelihood of your site generating sales (and commissions to your associate) will be greater than the competition’s.

Icon: There are no risks

There are no risks

As you will see later in this guidebook, all changes made in Conversion Optimization efforts must be certified by A/B testing. With this, science assures that you do not run the risk of making changes to your website that cause your conversion rate to decrease. The only way possible is up.

Icon: Your results can be like some of these companies

Your results can be like some of these companies

Check out what some of Supersonic’s clients accomplished after starting to invest in Conversion Optimization:

Chapter 3

How to begin optimizing your conversion rate?

Winning tests

Conversion Optimization has an excellent return on investment (ROI), but that doesn’t mean it’s an easy task.

Reality is relentless. According to a survey by Qubit,, 90% of all A/B tests do not bring any improvement and—even worse—sometimes impair website results.

Yes. This means that, on average, to have a winning test, you need to have nine other losing ones.

It is an alarming number, especially because it represents a much lower rate of success than we have at Supersonic.

But we believe that the huge amount of losing tests indicates that most people begin doing Conversion Optimization the wrong way.

You don’t start doing CRO by playing around with A/B testing. This is how you begin:

First step: collect data

As we’ve mentioned before, conversion optimization and personal opinions definitely do not go together.

Successful tests will seldom come from an idea someone had in the shower. Real results are found when you dig up as much data as possible to understand what is wrong or what can be improved on your site.

Even if you get an idea to change something on the site that won’t necessarily make results worse, there is a good statistical probability that it won’t make any difference on your conversion rate.

Let’s analyze the very real example of a test that usually leads nowhere.

Unfortunately, one of the first test ideas most people with no experience in CRO have is to change the color of the conversion button (or CTA—Call to Action). There’s nothing wrong with playing with colors. But the truth is, in most cases, people don’t fail to convert on websites because the button is orange instead of green. When was the last time you didn’t buy something on a website because of the color of the call to action button?

Ctas Comprar

This kind of “pointless” test happens often because people do not base their ideas on data.

And with the amount of readily available information today, there is no excuse to do so. Remember, you need to know what to change and why make the change.

Here are some examples of great sources of information to support your optimization ideas:

Google Analytics

You probably have Google Analytics installed on your site, right? It is the most popular clickstream tool in the planet. But if you have another tool for that, like Adobe Analytics), , it will work too.

The important thing is being able to understand how users navigate the site. Some analyses that can point out good insights are:

  • Landing pages with high rejection rates: users are landing on your site and leaving it without interacting with anything—the famous “rejections”? Why is this happening? It is possible that your page is not aligned with the expectations these users had when they clicked on the link that led them there. Try to strengthen as much as possible the bridge between where the user came from and the landing page.
  • “Gaps” in the conversion funnel: which pages do the users need to go through to convert on your site? Are many users abandoning the path on a specific step? Then you probably have a great opportunity for improvement.
  • Important but rarely visited pages: do you have a page that relays important information to convince the user to convert? Great! But… have you stopped to consider if this page gets a good number of visits? If the majority of users does not access a landing page with strategic information for conversion, it means the information is invisible to them. Try to emphasize this page or, at least, place the same fundamental information on highly visible sections of the site.

Heat Maps and Scroll Maps

If the topic seemed strange to you, learn more about Heat Maps and Scroll Maps with this article in our blog..

To begin, keep in mind that they are types of reports that show what draws the attention of users on a page—in other words, where they click or where they look. Here is an example:

Heat Maps and Scroll Maps

There are many tools that generate heat maps. Some of the most well-known are: Crazy Egg, Clicktale e Hotjar.

These reports, which we call heat maps or scroll maps, can identify insights like:

  • What interests the users or not: this is simple and powerful, but often overlooked. If your heat map shows a specific content getting a lot of clicks, it’s a sign that this information is important to your audience. Often, the high number of clicks can also mean that people want to know more. And what do you have to do? Give the people what they want, of course! Delve into what draws your users’ attention.
  • Where users lose interest in you: on a scroll map, you can tell exactly to which point the users scroll your pages to read the content. This type of report is ideal to learn where you are losing the users’ interest, causing them to stop interacting. Solve this problem by simply removing the questionable content or making it more attractive.

Usability Testing

Steve Jobs used to say:

“If a user is having a problem, it’s our problem.”

In the daily routine of a marketing professional, this should be more obvious than it really is.

Even those who do not agree with this statement need to accept an absolute truth: the more difficulty a user has navigating your site, the less likely he is to convert and become a customer.

So, we have no option: we need to ensure that any person with the potential to become our customer has the most intuitive and pleasant experience possible on our website.

And one of the most effective ways we know to ensure a good user experience (UX) is through usability testing.

From a simplistic point of view, usability testing is the act of watching a real user navigate your website. And as trivial as it may seem, several of our successful case studies owe a significant part of the results to usability testing (like this real estate company, , for instance).

If, during a test, a user shows difficulty navigating a site, surely several others are also experiencing the same problem. And this, as you can imagine, is extremely valuable insight.

You don’t need much more than a computer with internet capability to run a good usability test. But if you want to save these tests to analyze them with no rush later—which is recommended—you can use software like Camtasia (Windows) or Screenflow (Mac).

How to run a good usability test:

  • Ask the user to perform the actions necessary for conversion on your site.
  • Pay attention to the challenges presented by the user; to the mistakes he makes; to his questions, and even to more subtle reactions.
  • Do not do what many people do: interfere with his experience. Remember you are running tests to learn, not to teach.
  • Write down their insights and establish your adjustment priorities.

Simple, direct, and powerful. Believe us.

Chapter 4

The principles of an effective page

No. There is no secret recipe to create a high-conversion page. It would be perfect if there were, as it would save us many hours of work. But, unfortunately, this is not a reality.

However, there are some common characteristics in most pages that deliver good conversion rates. We listed some of them to inspire you to create or improve your pages:


If you’re not sure what the user needs to do on your page, how can you expect him to know?

Each page should intend to influence the user to do something. Consequently, the efforts of each page should be focused on bringing the user to carry out the proposed action.

Just to give you an idea of what not to do, we searched for “life insurance simulator” (an expensive term!) on Google and clicked on the most well-placed advertisement. This was the landing page:


We highlighted in red all of the elements on the page that are not related to the objective of those who get to it: to simulate or get an estimate for life insurance.

And, not only do they not meet the user’s needs, but many of these elements do something even worse: distract from the objective, directing visitors to various other pieces of information and paths that do not lead to conversion.

Identify the action that your user needs to carry out on one page. Then focus the content of the page on that action.

Be clear about what makes you unique

Why should I hire you instead of any of your competitors?

This is usually not an easy question to answer, isn’t it?

But, unfortunately, if your page can’t answer this clearly, it has not yet reached optimal performance.

One of the most powerful elements used to increase conversion rates is what we call the Unique Selling Proposition (USP). This is the term used to define what sets you apart—something only you do or something you do better than any competitor.

A great example of USP is what Domino’s Pizza did in an effort that turned out to be decisive for the growth of the company, which became the largest pizza chain on earth:


Domino’s promised to deliver their pizzas very quickly. And they bet so much on this distinctive quality that they decided to announce that they would not charge for the pizza if the delivery took longer than 30 minutes.

Since the speed of delivery is a critical factor for delivery service customers, this feature made Domino’s the priority choice for millions of people around the world.

So, are your pages exploring what sets your business apart as well as Domino’s did?

Invest in the title

The most important element of a page is the title.

And there is no shortage of numbers to prove this statement: on average, 80% of the people who access a page read its title. However, only 20% of them read the rest of the page. This, of course, makes the message conveyed by the title the most visible one on your page.

As if that weren’t enough, the title is usually the first element the user will read on your page. And, as you know, first impressions stick.

So, no matter what type of page you have, don’t scrimp on coming up with a good title.

And what makes a good title?

In this case, there is no magic formula. There are effective titles in several formats. However, every good title has this in common: it convinces the user to keep reading the page.

You can do this by instilling curiosity, presenting a good Unique Selling Proposition or drawing attention to a user’s pain. The roads may vary. Assess which one of them best fits your scenario.


Want more tips on how to build a page with a high conversion rate? Good news. We have a comprehensive guide to help you in every step of this mission:

Chapter 5

A/B Testing

This topic may be more popular on the internet than Conversion Optimization itself. Consequently, a lot of nonsense ends up being preached out there. Let’s start fixing it.

What is A/B testing?

A/B testing, in some cases also called “multivariate testing” or “A/B/n testing,” is much older than conversion optimization or the internet.

It is the most reliable way to prove a hypothesis. In fact, science only reached the heights it has today because it relies on A/B testing to assess proposed solutions to problems found.

Let’s consider a practical example: medication. How does science usually confirm whether a particular medicine is truly effective?

  • They gather a few volunteers who suffer from the problem that the medicine promises to heal.
  • The volunteers are divided into groups. For our example, we’ll consider two groups.
  • One of the groups will be the “control” group, receiving placebo doses as medication. In other words, nothing will change in their routine.
  • The other group will be effectively medicated with the medication being tested. They will receive the “real medicine.”
  • Finally, the results of the two groups are compared. “The hypothesis that the medication works will be accepted only if the group that received the ‘real medicine’ shows a higher percentage of improvement compared to the ‘control group.’”

The process above, which exemplifies A/B testing, is nothing more than what is known as the scientific method. It may be summarized as follows:


The history of the world has demonstrated that A/B testing is extremely effective. Then why not use it for our benefit in digital marketing? That’s exactly what conversion optimization is about.

Before permanently publishing any changes, you should run an A/B test.

What this test will do is very similar to the medication experiment described above. It will randomly divide the public that visits your site into two versions of your page: the current version, with the problem you identified, without any changes; and the updated version, with the solution you are proposing.

After a certain amount of people go through the pages, you will be able to identify, with statistical confidence, which version converted a higher percentage of visitors. Visually, it looks something like this:

Teste A/B

This way, you will always be scientifically sure of the effectiveness of any change you make on your site. Plus, you will also never implement something that might harm your conversion rates. And believe us: if there is one thing that even the most renowned faces in digital marketing do when they don’t run A/B testing, it is implementing changes that harm their conversion rates.

Today, there is no need to take that risk. So, assimilate this mantra into your life and become a much more effective professional:

Never again make any changes to your site without first evaluating them through A/B testing.

Tools for A/B testing

Ok. Ok. You understood what A/B testing is and why it is essential. But do you have questions about how to implement it? It’s simpler than it seems.

There are various tools that run the whole process of dividing your visitors at random between the pages being tested and measuring the conversions obtained by each version.

Let’s check some of them out!

Google Analytics

Google Analytics

Yes! The most popular Web Analytics tool in the planet has a feature that runs A/B testing. And it’s free! In the Behavior section, look for the “Experiments” item. There you will find everything you need to set up and track your A/B test.



Now it’s time for the paid tools. Optimizely does everything the A/B testing feature in Google Analytics does, but with an additional, interesting item: a visual page editor.

This means that you can implement a simple change in a page (changing the title, removing content, reorganizing elements, etc.) without involving web developers or editing any line of code. The tool will automatically test the original page in comparison with the changes you propose. A time-saving option for anyone who wants to grow quickly.

Visual Website Optimizer

Visual Website Optimizer

The Visual Website Optimizer (VWO) tool is similar to Optimizely, featuring a visual editor as the main attraction for those who want to run A/B testing.

Chapter 6

Case studies

One of the best ways to understand CRO and to gain insights on what to do in your own projects is reading case studies by companies that have managed to increase their conversion rates.

For this reason, we have set aside for you some of the cases we worked on with Supersonic’s clients. Each of these case studies explains in detail the whole process that led clients to reach new heights. So, enjoy!

Rock Content

How we increased conversions by 150% in one of Brazil’s largest startups

Casa Mineira

The new website that generated 7 times more contacts


How an e-commerce increased its revenue by 63%

Quality Training RH

A new product page and a 661% increase in the conversion rate


How a software company doubled its conversion rate

Chapter 7

Tips to start now and keep learning

Start now

Want to begin applying the lessons from this guide to optimize the conversion rate of your website? Then, the best thing to do is to download our e-book, which contains 30 CRO techniques you can implement today.

All 30 tips are easy to implement and have been tested through A/B testing in real situations. Don’t miss out on this content.

Book: 30 CRO techniques

Learn more

If you want to deepen your understanding of CRO and stay up-to-date on what’s new on this topic, you should subscribe to the Science of Conversion blog..

It is the first blog in Brazil that is completely focused on conversion optimization.

Você também pode fazer o download deste guia sobre otimização de conversão em PDF para compartilhar ele com todos seus contatos que precisam aumentar as vendas da empresa.

Blog: Ciência da Conversão - O 1º blog de Otimização de Conversão do Brasil

Need someone to optimize your conversions?

If you’re looking to hire someone to improve the conversions on your site, count on us. We are the first company that is specialized in CRO in Brazil, and we’ve delivered impacting results to various companies..

Let’s talk about your goals so we can understand how to help your business profit more!