Conversion Rate Optimisation
Conversion & UXAlso: CRO · conversion optimisation
Quick definition
The practice of increasing the percentage of website visitors who take a desired action — purchase, enquiry, sign-up. CRO uses data, user research and testing to systematically remove friction and improve outcomes without needing more traffic.
Where it shows up in the data
Running two versions of a page element simultaneously to see which performs better. The foundation of systematic CRO. Requires sufficient traffic to reach statistical significance.
Visual tools that show where users click, scroll to and where they stop. Essential for identifying friction before you hypothesise solutions.
Mapping where users drop off between steps. A 70% drop-off at checkout is different from a 70% drop-off on a landing page — both need fixing but with different approaches.
Surveys, interviews and usability tests that explain the 'why' behind quantitative data. CRO without qualitative input generates hypotheses without context.
What it actually means
CRO is the systematic process of getting more value from the traffic you already have. Most businesses focus almost entirely on driving more visitors and ignore the fact that small improvements to conversion rate compound dramatically. A site converting at 2% that improves to 4% doubles revenue without increasing ad spend. CRO combines quantitative analysis (where are users dropping off?) with qualitative understanding (why are they dropping off?) to generate and test improvements.
CRO is the discipline of treating your website like a hypothesis, not a finished product.
How to calculate it
Conversion Rate = (Conversions / Total Visitors) × 100
Worked example. Your landing page gets 2,000 visits per month and generates 40 enquiries. Conversion rate = 40/2000 × 100 = 2%. After redesigning the form (fewer fields, clearer CTA), enquiries rise to 74. New conversion rate = 74/2000 × 100 = 3.7%. You added 34 leads per month without changing ad spend.
The Australian context
Australian ecommerce conversion rates are broadly comparable to global benchmarks but tend to be slightly lower for cross-border shoppers unfamiliar with AU brands. Mobile conversion rates in Australia lag desktop by 35-50%, reflecting poor mobile checkout experiences across most mid-market retailers. This is one of the largest untapped CRO opportunities in the AU market.
Where people get this wrong
Related terms
Common questions
How much traffic do I need to run CRO tests?
As a rough guide, you need at least 1,000 visitors per variant per test to achieve 95% statistical significance at typical conversion rates. If you have less traffic, focus on qualitative CRO (user testing, surveys, heatmaps) rather than A/B tests. Low-traffic sites should prioritise fixing obvious problems over running controlled experiments.
What is the fastest CRO win for most businesses?
Simplifying the checkout or enquiry form. Removing unnecessary fields, adding trust signals (payment icons, security badges, reviews) near conversion points and reducing the number of steps to complete a purchase addresses the most common abandonment triggers.
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About New Rebellion
New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.
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