CRO: what conversion rate optimization really fixes
Conversion rate optimization means getting more of the people already on your site to buy, without paying for more traffic. The Baymard Institute measures an average cart abandonment rate of 70.22% and puts at 35.26% the conversion increase within reach by fixing usability problems it has already documented.
- It is the only lever that grows revenue without growing the acquisition budget. Doubling traffic costs twice as much; doubling the conversion rate costs nothing recurring.
- The average cart abandonment rate is 70.22%, compiled from 50 studies, and it has barely moved in twenty years.
- The Baymard Institute documents 140 causes of checkout usability problems. These are not hypotheses to test; they are known fixes.
- The average checkout displays 23.48 form elements by default, while a reduction of 20 to 60% is possible on most sites.
- CRO fixes neither a weak offer, nor a mispriced product, nor poorly targeted traffic. It amplifies what already exists.
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Conversion rate optimization
Conversion rate optimization, often called CRO, is the discipline of increasing the share of visitors who complete the intended action on a site, whether a purchase, a quote request or a booking, without increasing the volume of traffic. It rests on three sources: the usability problems already documented by research, the measurement of real behaviour on the site, and controlled experimentation. Its economic particularity is that a gain, once obtained, then applies to all future traffic, at no recurring cost.
Why it is the cheapest lever
The whole subject fits in one line of arithmetic. To double your sales, you can double your traffic, which doubles your acquisition budget, or double your conversion rate, which you pay for once.
A site that receives 20,000 visits a month and converts at 1.2% produces 240 orders. The same site at 1.8% produces 360, without one more dollar of advertising. On an average cart of $120, that is $14,400 in extra monthly revenue for a one-time project. It is also why raising bids before fixing the landing page is the wrong order, as Google Ads ROI details.
The figure that shows the scale of the opportunity comes from the Baymard Institute, which has been testing the checkouts of large companies for more than ten years. Limiting itself to the usability problems it has documented as solvable, it puts at 35.26% the conversion rate increase within reach for a large online commerce site. These are not hypotheses: they are known fixes, on sites already considered well built.
Two areas hold most of the gain on most sites: forms and the analysis of real behaviour rather than assumed.
What to settle before committing a conversion budget
CRO sells badly because it produces nothing visible: it creates no page, no campaign, no content. It makes frictions disappear. Yet it is the only work whose return then applies to all your paid traffic.
- What is our current conversion rate, by device, and how long have we tracked it?
- What would one more percentage point be worth in monthly revenue?
- Does our acquisition budget exceed what it would cost to fix the checkout once and for all?
- Who is allowed to change a checkout page, and how long does a decision take?
- If the rate has not moved after the work, what do we stop funding?
The useful answer first puts a number on the value of one conversion point for you, then starts from the already-documented problems before proposing tests. A weak answer sells a series of tests without measuring the starting point, promises a percentage gain before having seen the checkout, or talks about a redesign when the question is a friction.
Deciding whether your site loses sales to friction rather than to a lack of traffic is settled on your real numbers and a review of the checkout. A 90-minute consultation settles it, with a written summary your team can execute.
Where to look first
The order matters, because the first fixes are known in advance and require no testing.
| Order | Where to look | Why first |
|---|---|---|
| 1 | Costs shown late in the checkout | Surprise extra fees are the most cited reason for abandonment |
| 2 | The number of form fields | A reduction of 20 to 60% is possible on most checkouts |
| 3 | Forced account creation | It blocks a buyer ready to pay |
| 4 | The mobile path | That is where the conversion gap is widest |
| 5 | Form error messages | A poorly explained error makes a won customer leave |
| 6 | Only then, testing | Testing before fixing the known wastes traffic |
The most counterintuitive point is the last. CRO is often sold as a practice of constant testing, when most of the initial gain comes from fixes already documented by research. Testing what is known amounts to paying to rediscover it. Tests serve later, on what is specific to your market, and their method is covered in what an A/B test can conclude.
What stays in-house: the value of one conversion point for you, the average cart or sale, the margin, and the authorization to change the checkout. That last one is often the real bottleneck: in many companies, no one dares touch the page that takes the money. What gets delegated: reviewing the checkout against documented problems, measuring behaviour, prioritizing by expected effect, producing the fixes and designing the tests. A company that grants access to its checkout page earns more revenue than a company that orders a full redesign.
What CRO does not fix
This has to be clear, because it is the most frequent source of failure in these engagements.
CRO amplifies what exists. It does not fix an offer the market does not want, a badly positioned price, or traffic made of people who never intended to buy. A site that receives poorly targeted traffic will see its rate rise marginally and its revenue stay flat, because the problem is upstream.
One nuance shows it well. A share of abandoned carts comes from people who were simply browsing, with no intention to buy that day. No checkout fix converts them, and a vendor who promises to bring the abandonment rate near zero is promising something research describes as impossible.
A conversion rate is compared to your own history, never to an industry average. Definitions vary from one source to another, and so do average carts and buying cycles. A company that judges itself against an average found online makes budget decisions on a figure that does not measure the same thing as its own.
The continuity between the ad and the page is covered in the arrival page of a campaign, measurement in the three gaps that distort measurement, and the indicators that drive decisions in marketing indicators.
The particular case of an account-only space is covered in the B2B reordering portal.
Going further on conversion
Diagnosing. Cart abandonment: what the Baymard Institute's 49 studies show, Online merchants: the checkout frictions that cost you the most, Heatmaps: what they show, and what they do not prove, Online retailers: site search is the lever you are not measuring.
The enquiry and the form. Forms: the number of fields decides, not the number of steps, Manufacturers: have buyers configure before you ask for their contact details, Landing pages: message continuity before design, Online buyer psychology: what really triggers the decision.
Measuring. Conversion tracking: the three gaps that skew everything else, Marketing managers: what server-side tagging fixes, Multi-touch attribution: what actually remains possible, Quebec SMBs: what consent takes away from your measurement, A/B testing: why most tests prove nothing.
Sold by quote. How long do you have to call back a quote request?, Sold by quote: measure cost per sale, not per form, Retailers: the automated email sequences that pay, and the ones that wear out your list.
Turning a site into an asset that sells rather than a storefront is at the heart of the Improve your site's conversion goal.
Already running a marketing team? See how we plug in as reinforcement on conversion rate optimization.
Frequently asked questions about CRO
What gain can you expect from a conversion project?
The Baymard Institute puts at 35.26% the conversion rate increase within reach for a large online commerce site by fixing only the checkout usability problems it has documented as solvable. It is an order of magnitude drawn from tests on large companies, not a promise that applies as-is to a given site.
Why are 70% of carts abandoned?
The average rate of 70.22%, compiled from 50 studies, aggregates very different causes. A significant share comes from people who were browsing with no intention to buy that day, and whom no fix will convert. The rest is documented frictions, including fees discovered late and the length of the checkout.
Should you start with A/B tests?
No, usually. Most of the initial gain comes from fixes already documented by research, which do not need to be rediscovered. Tests cost traffic and time, and they serve later, on what is specific to your market rather than on what everyone already knows.
How many fields should a checkout form have?
Fewer than it probably has. Baymard measures an average of 23.48 form elements displayed by default in a checkout, and estimates that a reduction of 20 to 60% is possible on most sites. Each field removed is one less obstacle between a decided buyer and their order.
- Baymard Institute, Cart abandonment rate statistics, average compiled from 50 studies, accessed July 2026.
- Baymard Institute, research on checkout usability, tests conducted over more than ten years on large US and European sites, accessed July 2026.
Gabriel almost always takes your first call and carries out your audit. He builds the strategy starting from your growth goal: where to put your budget, which market to test and how to connect each lead to a real sale in your CRM. He mainly leads engagements for three goals: Optimize the profitability of your digital campaigns, Develop a new market, and Generate demand and growth. With Geneviève, he also works on organic search (SEO), AI visibility (GEO) and conversion rate optimization (CRO). The sales a Google Ads or Meta Ads campaign brings in depend on the page that receives the click. He writes mainly about marketing strategy, paid advertising and measurement.
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