CRO Glossary

The average amount spent per transaction — a key revenue metric multiplied directly by conversion rate to calculate overall revenue.

The percentage of customers or subscribers who cancel or stop using a product within a given period — the primary retention metric.

The percentage of people who click a link, ad, or CTA out of the total who saw it — a key engagement metric in CRO and paid media.

The percentage of website visitors who complete a desired action — a purchase, sign-up, or form submission.

The total cost to acquire one paying customer — all sales and marketing spend divided by new customers gained in the same period.

The total revenue a business can expect from a single customer over the entire relationship — a core metric for CRO budget and acquisition decisions.

The average revenue generated by each website visitor — the single metric that unifies conversion rate and average order value.

A controlled experiment comparing two versions of a webpage to determine which produces more conversions.

A range of values within which the true effect of an A/B test variant is likely to fall — more informative than a single point estimate.

The smallest improvement in conversion rate that an A/B test is designed to detect — the key input that determines required sample size.

A testing method that tests multiple page elements and combinations simultaneously — more complex and traffic-intensive than standard A/B testing.

The probability that an observed test result occurred by random chance if there is actually no real difference between variants.

A test quality issue where the actual traffic split between variants differs from the intended split, indicating randomization failure and invalidating results.

The probability that an A/B test correctly detects a real effect when one exists — typically set at 80%, meaning 20% chance of missing a real winner.

A statistical threshold confirming that a measured difference between A/B test variants is unlikely to be due to random chance.

The percentage of visitors who leave a website after viewing only one page without taking any action.

The percentage of sessions that ended on a specific page — different from bounce rate, as exits can follow multiple pageviews within the session.

A visual analytics tool that uses colour gradients to show where visitors click, move, and scroll on a webpage.

A tool that records video replays of real user sessions — showing clicks, scrolls, and rage clicks to reveal why visitors aren't converting.

URL tracking tags appended to links that tell analytics tools exactly where each visitor came from — essential for accurate conversion attribution.

The portion of a webpage visible without scrolling — the highest-value real estate on any landing page where first impressions are made.

A prompt that directs visitors to take a specific, desired action — a button, link, or form that initiates conversion.

When an e-commerce shopper adds items to their cart but leaves without completing the purchase.

The complete sequence of interactions a customer has with a brand — from first awareness through purchase, onboarding, and retention.

Any element in the conversion path that slows, confuses, or discourages a visitor from completing the desired action.

The process of improving each stage of a conversion funnel to reduce drop-off and increase the percentage of visitors who reach the final goal.

A standalone web page designed for a single conversion goal, typically reached via an ad, email, or direct link.

The alignment between the copy in an ad or email and the headline of the landing page it links to — the single biggest driver of post-click conversion.

A small, intermediate action a visitor takes on the path to the primary conversion goal — newsletter signup, video play, or add-to-cart before purchase.

Delivering different content, offers, or experiences to different visitor segments based on their behavior, source, or characteristics.

A CRO prioritization model that scores potential tests by Potential, Importance, and Ease to identify the highest-ROI experiments to run first.

Elements that reduce visitor scepticism and build confidence — reviews, security badges, guarantees, and credentials that directly improve conversion rate.

A clear statement explaining what benefit a product delivers, for whom, and why it's better than alternatives — the core message of any landing page.

A cognitive bias where the first number or piece of information encountered disproportionately influences all subsequent judgments.

The mental effort required to process a page. High cognitive load kills conversions — visitors leave rather than work to understand your offer.

A pricing strategy where a third, inferior option is added to make one of two existing options appear significantly more attractive.

The anxiety that others are having rewarding experiences you're excluded from — a powerful conversion driver when used authentically.

A cognitive bias where the same information presented differently leads to different decisions — how you say it matters as much as what you say.

A cognitive bias where a positive impression in one area influences overall judgment — brand credibility transfers across all site elements.

A cognitive bias where losing feels twice as painful as gaining feels good — used in CRO to frame offers around what visitors stand to lose.

The phenomenon where too many options reduces decision-making ability, increases anxiety, and lowers conversion rates.

A psychological effect where early exposure to a stimulus influences responses to subsequent stimuli — first impressions shape the entire visitor experience.

A persuasion principle that increases perceived value and urgency by limiting availability — of quantity, time, or access.

A psychological principle where people look to others' actions to guide decisions — used in CRO via reviews, testimonials, and customer counts.

Google's set of three performance metrics — LCP, INP, and CLS — that measure page experience and directly influence both search rankings and conversion rates.

A Core Web Vitals metric measuring visual stability — how much page elements unexpectedly move around while loading, frustrating visitors and causing misclicks.

A Core Web Vital that measures how long it takes for the main content of a page to load — the primary page speed metric for SEO and UX.

How quickly a web page loads and becomes usable — directly affecting bounce rate, conversion rate, and search engine rankings.