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Keeping abreast of conversion optimization trends and technologies can be tiring. Even more so when the terms/keywords used by conversion experts are going over your head. This glossary aims to help you by bringing all popular CRO terms — basic as well as advanced — in one place. To make the list comprehensive, the terms have been compiled from a wide range of conversion optimization disciplines such as A/B testing, Website Design, Online Ads, SEO, and more.


A/A Testing

A/A testing is a method of experimentation where two versions of a webpage (or the same version) are shown to a specified set of visitors and compared to test the accuracy of a testing tool.

A/B Testing

A/B testing is an experiment where two versions of a web page are compared to see which one drives more conversions.

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A/B/n Testing

A/B/n testing is a method of experimentation where, unlike A/B testing, you compare more than two versions of your webpage to identify which one performs best by showing them to a specified set of visitors.

Above the Fold

In the digital world, ‘above the fold’ in a website means the content a visitor sees when your page loads before they scroll down.

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Account-based Marketing

Account-based marketing (ABM) is a strategic marketing strategy focussing on a few large and important or potential accounts which hold a greater promise of adding to a business's bottom line.

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Ad Viewability

Ad viewability looks at the number of ads served by digital advertisers actually getting seen by users.

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Affiliate is a website that promotes another company’s products or services on its space and earns a commission from it. This practice is known as Affiliate Marketing.

Alt Text

Alt Text is an HTML attribute used to describe the appearance and role of an image element to enhance website accessibility. Search Engines rely on this to identify what the image element is when it is not rendered.

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Anchor Text

Anchor text is the clickable text on a hyperlink. Best practices for SEO advise that anchor text should be closely related to the web page it links to.

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AOV is an acronym for Average Order Value. As the name suggests, it is the average value (typically in dollars) of all orders processed by an ecommerce store.

App Personalization

App personalization is the process of building apps in such a manner that it caters to the needs of specific visitor segments.

Application Programming Interface (API)

An interface/intermediary that allows two applications/programs to talk to each other.

Authority Site

Authority sites are the websites that the search engines consider to be of high-quality.

Average Order Value

Average order value (AOV) refers to the average amount of money spent by a customer when they place an order on a website, mobile app, or in-store.

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Baseline conversion rate is the existing conversion rate of a website, which an A/B test attempts to improve.


Bayesian is a probability concept that interprets probability as a degree of belief. In A/B testing, Bayesian probability offers an absolute level of a test result's validity.

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Behavioral Targeting

Behavioral targeting is an advertising strategy where websites present their visitors with ads that are specifically related to their interests and preferences. Websites can do this by tracking a visitor’s shopping and browsing history.

Below The Fold

Below the fold is that portion of a web page that is visible only when a user scrolls on a page after landing on it.


When a visitor arrives on a website and leaves without viewing other pages on the website, it is called a bounce.

Bounce Rate

Bounce rate is the percentage of visitors that end up bouncing from a website. It is often used as a measure to check a website’s effectiveness. A website’s higher bounce rate reflects its lack of ability to engage visitors.

Brand Engagement

Brand Engagement is the process of building and sustaining a customer’s commitment/attachment to a brand.

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Bucket Testing

Bucket testing is synonym for A/B testing.


Call To Action (CTA)

A Call to Action is an instruction given to website visitors that provokes an immediate response. Any action that a website wants its visitors to perform is carried out using a CTA button. And hence, it is one of the hottest website elements that are A/B tested.

Campaign Scheduling

Campaign scheduling is a feature that allows the user to start/pause campaigns automatically for certain periods of time. For example, a test campaign that should run only on a specific day of the week. This does not apply to always-on features like Heatmaps and Recordings.

Canonical URL

If there are multiple URLs through which a web page can be reached (like and, the search engine picks up the preferred URL defined by the webmaster. This preferred URL is known as a canonical URL.

Cart Abandonment

Cart abandonment is the phenomenon that occurs when website visitors initiate the purchase process of a product, add it to the cart, but don’t buy it at the end. It is one of the biggest pain areas for ecommerce players.

Churn Rate

Churn rate is the percentage of customers of a service that discontinue using the service in a specific interval of time. A high churn rate often indicates that a company's services are not satisfactory. Churn rate is also known as Attrition Rate.

Click Area

A type of insight report classified under website heatmaps that provides numerical data about clicks on various elements opposed to visually representing them as hot-zones.

Click-Through Page

Click-through page is a web page that is placed before a website’s main ac,on-page (like a shopping cart page for an ecommerce website). Its purpose is to prepare visitors for a conversion on the next page.

Click-Through Rate (CTR)

Click-through rate is the percentage of clicks on a button or a link, out of the total number of visitors who saw it. CTR is used to determine the success rate of a campaign or a web page.


Click-to-call is a CTA button on a mobile website/application that allows visitors to call a phone number directly.


Clickbait refers to the sensationalized low-quality content on the internet, whose main purpose is to attract visitors and generate revenue from ad clicks.


Clickmap is a type of website heatmap. It shows the number of clicks for each link/element on a website.


Clickstream is the list of links that a visitor clicked on, during their stay on a website. Clickstream is used to determine the interests and site preferences of a visitor.

Client Side Testing

Client side testing is a method of running tests where the entire experiment is hosted on the client-side, i.e. natively on a browser plugin or web browser. A/B testing, Split-URL testing, multivariate testing are some methods of client-side testing.


Content cloaking is the act of showing different content to search engine bots and actual human visitors.

Code Editor

Code editor is a version of the editor that is used to create variations for test campaigns purely with code and not by adjusting/adding elements visually.

Confidence Interval

A confidence interval is the estimated value of a metric plus and minus the variation in that estimate.

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Confidence Level

Confidence level is the probability that a variation in an A/B test won not because of chance.

Content Management System

CONTENT MANAGEMENT SYSTEM is a web-based application that allows people to easily (without any coding involved) add/update text and multimedia content on a website.

Content Marketing

Content marketing the practice of creating and popularizing text and multimedia content for a business to attract and retain customers.

Control Page

Control page is the website's existing page that is piNed against its variation(s) in an A/B test.


Conversion is the action that marketers want a website visitor to take. Newsletter sign-ups, account registrations, and product inquiries are generally considered as micro-conversions. A monetary transaction is generally considered as a macro-conversion.

Conversion Funnel

Conversion funnel is the path intended for a visitor to take on a website for them to convert from potential customers to customers.

Conversion Rate

Conversion rate is the percentage of visitors who have completed a conversion.

Conversion Rate Optimization (CRO)

Conversion rate optimization is the practice of continually improving a website’s ability to affect conversions.


Cookies are small files that are stored within a web browser of a computer. Cookies have information related to a user’s visit to specific websites. Cookies are used to track users’ browsing history and site preferences.

Cost Per Acquisition

Cost per acquisition is the total cost of converting a website visitor into a paying customer.

Cost Per Click (CPC)

It is a payment model for online ad campaigns. CPC is the amount that an ad owner pays every time a visitor clicks on their ad


CPM or cost per million impression is the amount that an ad owner pays when the ad is displayed for a thousand times.

Crawlers (Spiders)

A web crawler is an internet bot that browses the entire world wide web and indexes websites into a directory.

CRM System

CRM is an acronym for Customer Relationship Management. A CRM System is an enterprise-grade software that contains the history of a company's interaction with all its customers via multiple channels.

Cross-Domain Tracking

Cross-domain tracking is the ability of tracking devices to connect sessions from two separate websites domains in an attempt to attribute behavior to the same user.


Cross-selling is the practice of selling complementary products to existing customers. It is a popular practice among marketers because selling to an existing customer is a lot easier than selling to a new prospect.

Custom Conversion

Custom conversion is a goal type that allows users to track custom events that are not triggered by clicks/page visits. This goal type will trigger a javascript code snippet when the condition is fulfilled.


Date-Range Filters

Date-range filters is the ability to filter a report for a specific date range. For example, view a Goal’s conversion report when a marketing campaign was live for a week on the website.

Directional Cues

Directional cues are visual elements of a website that are used to direct visitors’ attention to a specific area on the website (a CTA or an information box).

Do Not Track

Do not track is a browser setting that communicates to websites that visitor’s internet usage should not be tracked by analytics tools, although many websites might still collect some data to improve security, serve relevant ads, and so on.


Drop-off is a field-level metric in a form analytics report that shows the number of visitors that dropped-off from filling up the form from that specific field.

Dynamic Content

When a website serves distinct content to different visitors (based on their demographic attributes), the content is referred to as dynamic content.

Dynamic Heatmap (Browsable heatmap)

A very powerful implementation of website heatmaps that overlays click data in the form of hot-zones directly on the live-webpage, as opposed to a screenshot of the page in ‘static heatmaps.’ This ensures that click data is not shown for outdated versions of the page (if an element is removed or changed or moved). Additionally, a user can look at data on hidden elements (like drop-down menus) and be able…


Elements List

Element list is a report type under website heatmaps that shows the list of elements on a page sorted by its relative importance in terms of clicks it has received.

Email Marketing

Email marketing is a practice where businesses use email as a medium to nurture their leads and retain their customers. Sending personalized and value-packed emails help push conversions.

Exit Pop-Up

Exit pop-up is a pop-up that is displayed on the screens of website visitors as soon as they show an intent to leave the website. Exit pop-ups generally carry some sort of incentive for visitors, encouraging them to engage more with the website.

Exit Survey

Exit survey is a small set of questions that ask visitors about their website experience when they try to leave the website.

Experience Optimization

Experience optimization is the process of testing and optimizing a website so that visitors get the best possible experience across all touchpoints throughout the website journey.

Eye Flow

Eye flow is the study of visitors’ eye movements while browsing a website. Eye flow helps to track areas that visitors view or discard the most.


Feature Flag

Feature flag is a method that allows teams to modify the experience of a visitor of a website or a web application by turning on/off specific features or sub-sections.

Feature Rollout

Feature rollout is the process of introducing new features in a web application to users in a staged manner.

Feature Testing

Feature testing is the practice of making changes in a web application to introduce new features with a limited reach or modifying existing features to analyze the impact on the bottom-line.

Field Level Statistics

Field level statistics is that part of a form analytics report that provides insights on the performance of individual fields in terms of time spent, refills, ignores, etc.

Form Analytics

Form Analytics is a research capability that helps assess the performance of forms on a webpage.

Form Testing

Form testing is the practice of A/B testing forms on a website.


Friction is caused by elements of a website that confuse or distract visitors, resulting in a loss of conversions. Friction-causing website elements can be complex navigation links, cluttered boxes, CTAs with a lack of visual contrast, etc.


A conversion funnel is a marketing model that illustrates all steps taken by a customer towards purchasing a product from a website.

Funnel Testing

Funnel testing involves executing A/B tests across all web pages of a website funnel.



Gamification is the practice of introducing game-style offers to potential/existing customers. The idea is to encourage them to complete more transactions — in a fun and engaging way. Loyalty program is an example of a gamification strategy.

General Data Protection Regulation (GDPR)

GDPR is an important regulation that safeguards the usage of Personal Identifiable Information (PII) to protect the privacy of European website visitors' personal information.


Geo-fencing is the practice of targeting users based on their location. It involves using GPS/map technology to create a virtual boundary around a physical location and sending targeted messages to users when they enter the area.


Geo-targeting is the process of delivering customized content to visitors based on their geography.

Growth Hacking

Growth hacking is the use of low-cost and innovative marketing techniques combined with search engine optimization, website analytics, content marketing, and A/B testing to increase a business' popularity and conversions.



Heatmap is a graphical representation of the most engaging areas of a website.

Hero Image

Hero image is the most prominent banner or image present on a website. The hero image is usually the first visual of a website that visitors encounter.

Hesitation Time

Hesitation time is a field-level stat in a form analytics report that shows the time spent by the visitor on the field when they were not actively filling it up.


Hypothesis is an idea arising from observing behavior patterns of visitors in an attempt to improve the performance of the website. The hypothesis is then tested to prove or disprove it by understanding the impact of the change on goals associated with it.

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The number of times an ad is displayed to online visitors is counted as impressions.

Information Scent

Information scent helps visitors predict what kind of information they are likely to get from your website in the next scroll/scrolls, clicks, and so on by navigating a page.


Interruption is a practice of providing attention-grabbing content to website visitors that purposely breaks their usual website navigation experience. Exit pop-ups can be considered as a form of interruption.


JS Variable

JS variable is a targeting condition that evaluates a custom criteria using javascript variables defined on a page.


Landing Page

Landing page is the web page that visitors are directed to when they click on an ad (or a link from a campaign). A landing page can be a lead generation page or a click-through page.

Landing Page Optimization

Landing page optimization is the process of optimizing landing page elements by various conversion increasing methods like visitor behavior research, A/B testing, and so on.

Latent Conversion

When visitors complete a conversion on their follow-up visit to a webpage (and not on the first visit itself), it is known as a latent conversion.

Lead Generation

Lead generation refers to generating visitor interest into a product or service with the aim of converting that interest into a sale.


Leads are potential customers for a business who have already shown interest by providing their contact information — permitting the company to contact them.

Lifetime Value

Lifetime value is the total profit that a business is expected to earn from a customer over their entire future relationship with the company.

Live Chat

Live chat is a real-time chat-based customer support service that websites provide to their visitors.

Long Tail Keywords

Long tail keywords are search phrases that usually include more than three words. Long-tail keywords describe a search query comprehensively.


Meta Tag

Meta tag is an HTML tag that allows webmasters to insert text description of a web page. The meta description for web pages appears with their links in search engine results.


microsite s a small website — usually different from a company’s main website — that has succinct content and is related to a specific campaign.

Mobile App A/B Testing

Mobile app A/B testing is an experiment where two versions of a mobile app are compared to see which one drives more conversions and delivers the better user experience.

Multi-Armed Bandit Testing

Multi-armed bandit testing is a more complex version of A/B testing. It leverages machine learning algorithms and dynamically allocates traffic to versions of your webpage that are performing well, and in turn allocates less traffic to underperforming variations.

Multivariate Testing

Multivariate testing is the practice of testing multiple variations of a web page - for more than one element - to determine which version results in higher conversions.


Null Hypothesis

Null hypothesis is the hypothesis that an A/B test tries to disprove. The null hypothesis states that the conversion rates of control and variation(s) are the same.


On-Page Surveys

On-page surveys are surveys that are run on active website visitors whereby questions are asked from users while they are on the website. It is a method of qualitative visitor research aimed at identifying friction sources basis real-time website experience.

Organic Traffic

Organic traffic is the traffic coming to a website through non-paid search engine results.



Personalization is the practice of customizing web pages (or any other digital content) to match individual visitors' interests and preferences.

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Proximity is a web designing practice that directs a webmaster to group similar or related website elements together, and place unrelated or dissimilar elements apart.


Qualitative Visitor Research

Qualitative visitor research involves the use of research tools like heatmaps, session recording, form analysis, and so on to track and analyze visitors’ browsing pattern on a webpage or website based on their real-time behavior. It allows you to gauze beyond just numbers and dive deep into visitors’ behavioral pattern to glean valuable visitor behavior insights.

Quantitative Visitor Research

Quantitative visitor research involves the use of research tools like Google Analytics to gather numerical data on your website performance. This method provides the exact numerical data on a website or webpage’s conversion rate, bounce rate, average session time, and other such quantifiable data.


Responsive Website Design (RWD)

A website with responsive design adapts its layout to that of the viewing environment (mobile, desktop or tablet) to provide an optimum viewing experience to visitors.


Retargeting is the practice whereby website visitors are shown ads/banners about the things they earlier browsed but didn't convert. Retargeting is used to push those visitors for a conversion who have already shown some interest in the website.

Revenue Per Visitor (RPV)

Revenue per visitor or RVP is the average revenue that a website earns from each of its visitors. RPV is considered as the most appropriate metric that is used to measure an ecommerce store’s performance.


Sample Size

Sample size in A/B testing is the set of visitors that determine the conversion rate of different variations of a website.


Scarcity is a psychological tactic that marketers use to push visitors towards a conversion action. It takes advantage of the human fear of 'shortage' or in today's terms, FOMO (fear of missing out) - “Only 5 items left” and “Sale only till 8 PM” are some examples where scarcity marketing is used.


Scrollmap is a type of website heatmap that visually represents visitors’ scrolling behavior on a webpage. It indicates how far users scroll down a page as well as which sections they spend the most time in.


Segmentation refers to the practice of identifying certain visitor behavior traits, creating corresponding segments, and grouping visitors with similar behavioral traits into the same segment. Segmentation helps in running successful targetted campaigns for increased conversions.


SERPs is an acronym for Search Engine Result Pages. The ultimate goal of SEO strategies is to make websites appear on the top of a SERP.

Server Side Testing

Server side testing is the practice of testing variations by directly rendering them on the server itself to a defined audience segment. This is most suitable for testing product features before rolling them out to the entire audience base.

Session Recording

Session recording is a method of gathering qualitative visitor insights. Session recording records all the actions that a visitor takes on a website from clicks and scrolls to mouse movement, page shifts, and much more. In short, it records visitors’ end-to-end browsing session on a website.

Social Proof

Customer testimonials, product reviews, and trust badges make up the social proof of a website.

Split Testing

Split testing is a synonym for A/B testing.

Split-Url Testing

Split URL testing involves testing multiple versions of a webpage that are hosted on different URLs. Split URL testing is best suited when there are major design changes on the web page.

Standard Error

The degree to which the result of an A/B test can be apart from the actual figure is called standard error.

Statistical Significance

Statistical significance determines the validity of an A/B test.

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Test Duration

Test duration is the specific time period over which an A/B test is run. It is imperative to determine the minimum test duration of an A/B test for reaching a conclusive result.

Test Hypothesis

Test hypothesis is a tentative assumption that changing a specific element(s) of a website will lead to higher number of conversions. Establishing a test hypothesis is the first step towards executing an A/B test.

Title Tag

Title tag is an HTML tag — a part of meta tags — that defines the title of a web page. A web page's title tag is displayed above its meta description in SERPs.

Trust Badges

Trust badges are small logos or icons that convince visitors about the safety and credibility of the website.

Type-1 Error

When a null hypothesis (representing no effect) is rejected during hypothesis testing process, even if it is accurate and should not be rejected by the test, it is called a Type-1 error or a False Positive. A null hypothesis is defined before the start of an A/B test or MVT which represents no difference between the variations being tested. 

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Unique Visitors (UUID)

Unique visitors is the number of distinct visitors of a website out of its total traffic. Unique visitors are tracked using cookies.


Upselling is a practice of offering a higher value (and usually more expensive) product/service to an existing customer.


Usability refers to the ease of use of a website. The usability of a website can be tested by hired experts, who thoroughly analyze the website and provide suggestions for improvement.

User Generated Content (UGC)

User generated content is content in the form of text, images, and videos that are submitted by users to a website as a part of some campaign.

User Intent

User intent is the end goal that a user wants to fulfill through submitting queries on search engines. Understanding user intent is imperative for ranking well in search engines. This is how the focus on SEO is changing from keywords to user intent.

User Intent

User intent is the end goal that a user wants to fulfill through submitting queries on search engines. Understanding user intent is imperative for ranking well in search engines. This is how the focus on SEO is changing from keywords to user intent.

User Testing

User testing is the practice of testing the usability of a website with the help of real people. User testing can be done in the following ways: 1. By inviting potential users to use your website, and observing the problem areas in usability. 2. By evaluating a website based on the behavior of real visitors — using tools like clickmaps and heatmaps. (The users are not aware that their website…


Web Push Notification

Web push notifications are clickable pop-up messages that appear on your users’ browsers irrespective of which device they use or which browser they are on. Subscribers can be anywhere on the browser and still receive these messages as long as they are online or have their browsers running on their devices.

Website Banner

Banners are rectangular segments (of various dimensions) on a website that are generally used to display ads.


Whitespace is a design strategy which involves using blank spaces for directing attention towards a valuable website elements such as a CTA.


They are small application boxes that typically fit in one of the side banner areas of a website. The use of widgets vary in a range of functions like providing navigation links, submission of forms, and more.



Z-index is a css parameter that measures how elements are stacked when they overlap.

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