Short answer

The conversion rate optimization statistics most worth knowing come from their original sources: Baymard Institute's average documented cart abandonment rate is 70.22%, extra costs revealed late are the most common avoidable reason, and Optimizely's data on more than 127,000 experiments shows around 12% winning on their primary metric. Use them as context, then measure your own baseline.

  • Each statistic on this page was checked in its original source, with its year and what it actually measures.
  • The most quoted page speed figures show association, not cause; Bing's controlled experiments are the stronger evidence.
  • Landing page benchmarks put very different goals in one average, so a median says little about your page.
  • Popular statistics whose original could not be opened, or does not say what is quoted, are left out.
  • Your own baseline is the only conversion rate you can act on.

How these CRO statistics were chosen

Each CRO statistic on this page was found in its original source, not copied from another list. The source is linked, the year is shown, and the note says what the number actually measures: a survey answer, a model estimate, a vendor's own customer data or a controlled experiment. Where the popular version of a statistic differs from the original, the original wins.

  • Primary sources only. The study, report or paper itself, or the publisher's own research page.
  • The year is the source's year. Some figures are old and still the best available; the year lets you judge.
  • Caveats stay attached. Sample, method and who funded the research are noted where they matter.

Key conversion rate optimization statistics

The ten conversion rate optimization statistics most worth knowing: about 70% of online carts are abandoned, extra costs are the top avoidable reason, most A/B tests do not win, small speed gains are associated with more conversions, and reviews raise purchase likelihood. Sources and years are in the full tables below.

  • 70.22% is the average documented online shopping cart abandonment rate, across 50 studies (Baymard Institute, 2025).
  • 40% of US shoppers who abandoned for a reason other than browsing cited extra costs such as shipping, tax and fees (Baymard Institute, 2025).
  • 35.26% is Baymard's estimate of the conversion rate increase an average large ecommerce site could gain through better checkout design (Baymard Institute, 2025).
  • 6.6% is the median landing page conversion rate across all industries in Unbounce's data (Unbounce, 2024).
  • Around 12% of experiments won on their primary metric, across more than 127,000 experiments (Optimizely, 2018 to 2023 data).
  • About one third of ideas tested at Microsoft improved the metrics they were designed to improve (Kohavi et al., 2009).
  • 8.4% more retail conversions were associated with a 0.1 second mobile site speed improvement (Deloitte, 2020).
  • 32% is the increase in the probability of a mobile visitor bouncing as page load time goes from one to three seconds (Google, 2017).
  • 270% greater purchase likelihood for a product with five reviews than for one with none (Spiegel Research Center, 2017).
  • 17.1% of total US retail sales were e-commerce in the second quarter of 2026, seasonally adjusted (US Census Bureau, 2026).

Cart abandonment and checkout statistics

Cart abandonment statistics come mostly from Baymard Institute, which averages published abandonment studies and runs its own shopper surveys and checkout usability benchmarks. The average documented abandonment rate is 70.22%, and the most common avoidable reason is extra costs revealed late. Many causes are design problems a store can fix.

Cart abandonment and checkout statistics, with sources
StatisticSource and yearWhat it measures
70.22% average documented online shopping cart abandonment rateBaymard Institute, cart abandonment rate list, last updated 2025An average of 50 third-party studies dated 2006 to 2025, with different methods
42% of US online shoppers have abandoned a cart because "I was just browsing / not ready to buy"Baymard Institute, 2025Self-reported survey of US online shoppers
40% cited extra costs too high (shipping, tax, fees)Baymard Institute, 2025Share of abandoners, excluding the "just browsing" group. The reasons below are on the same basis
20% said delivery was too slowBaymard Institute, 2025Same survey
19% did not trust the site with their credit card informationBaymard Institute, 2025Same survey
18% left because the site wanted them to create an accountBaymard Institute, Checkout UX benchmark, 2025Survey of 1,026 US adults who had shopped online in the previous 3 months
17% cited a too long or complicated checkout processBaymard Institute, 2025Same survey
12% could not see or calculate the total order cost up frontBaymard Institute, 2025Same survey
9% said there were not enough payment methodsBaymard Institute, 2025Same survey
35.26% potential conversion rate increase for an average large ecommerce site through better checkout designBaymard Institute, 2025Baymard's estimate from its usability research, not a measured lift on real sites
23.48 form elements in the average US checkout flow (14.88 counting only form fields), against an ideal of 12 to 14 (7 to 8 fields)Baymard Institute, 2025Baymard's checkout benchmark database of US sites
64% of leading US and European ecommerce sites have "mediocre" or worse checkout UX, and only 2% rate "good"Baymard Institute, Checkout UX benchmark, 2025Expert benchmark of leading sites against Baymard's guidelines
62% of sites fail to make guest checkout the most prominent optionBaymard Institute, 2025Same benchmark
32% of test participants did not complete at least one required field when a form marked only its optional fieldsBaymard Institute, 2025Usability testing observation

What to do with it: show shipping, taxes and fees before checkout, make guest checkout the obvious choice, cut fields, and label both required and optional fields. The checkout optimization guide and the guide to the cart abandonment rate go further.

Page speed and conversion statistics

Page speed statistics consistently link slower pages with fewer conversions and more bounces. The strongest evidence comes from controlled experiments at Bing; the most quoted figures come from observational studies by Google, Deloitte and Akamai, which show association rather than cause. All of them point the same way: on mobile especially, fractions of a second matter.

Page speed and conversion statistics, with sources
StatisticSource and yearWhat it measures
A 0.1 second mobile site speed improvement was associated with 8.4% more retail conversions and 9.2% higher retail average order valueDeloitte, "Milliseconds Make Millions", 202037 brands, 30 million sessions over 4 weeks, Europe and US. Commissioned by Google. Observational, analyzed with a regression model
The same improvement was associated with 10.1% more travel conversionsDeloitte, 2020Same study
As mobile page load time goes from 1 to 3 seconds, the probability of a bounce increases 32%Google/SOASTA Research, 2017A neural network prediction. A relative increase in bounce probability, not a 32% bounce rate
From 1 to 5 seconds, the probability of a bounce increases 90%; from 1 to 10 seconds, 123%Google/SOASTA Research, 2017Same model
A 100 millisecond delay in website load time can hurt conversion rates by 7%Akamai, Online Retail Performance Report, 2017About 10 billion visits to top online retailers over one month. Correlation, from the press release
A two second delay in page load time increased bounce rates by 103%Akamai, 2017Same data
At Bing, every 100 milliseconds of speed improvement increased revenue by 0.6%Kohavi et al., "Online Controlled Experiments at Large Scale", 2013Controlled experiments on Bing, a search engine with very high traffic

What to do with it: test your key pages in PageSpeed Insights and on a real phone on mobile data, fix the slowest templates first, and measure conversion before and after. See mobile conversion optimization.

Landing page conversion rate statistics

The largest published landing page benchmark is Unbounce's Conversion Benchmark Report. Its 2024 edition puts the median landing page conversion rate across all industries at 6.6%, with industry medians from 3.8% to 12.3%. Each page counts its own goal, so a newsletter signup and a sales inquiry sit in the same average.

Landing page conversion rate statistics, with sources
StatisticSource and yearWhat it measures
6.6% median landing page conversion rate across all industriesUnbounce, Conversion Benchmark Report, 2024More than 41,000 landing pages, 464 million unique visitors and 57 million conversions, all on Unbounce customers' pages
Industry medians range from 3.8% to 12.3%Unbounce, 2024Same data, split by industry
83% of the landing page visits analyzed happened on mobile devicesUnbounce, 2024Same data

What to do with it: use the median as context, not a target, and check your landing pages on mobile first, since that is where most of the visits in this data happened. See landing page optimization.

See where your own site stands

Benchmarks describe other people's sites. Convertica's free CRO audit app checks yours: eight checks for people and AI agents, each scored out of 100. Enter your website and watch it run live.

A/B testing statistics: how often tests win

A/B testing statistics from the companies that run the most experiments agree on one point: most tests do not win. Optimizely's data on more than 127,000 experiments shows around 12% winning on their primary metric, and Microsoft researchers found that about one third of ideas improved the metric they targeted. Conversion rate testing works by finding the few changes that do.

A/B testing statistics, with sources
StatisticSource and yearWhat it measures
Around 12% of experiments win on the primary metric; 88% do notOptimizely, "Evolution of experimentation", data 2018 to 2023Over 127,000 experiments on Optimizely's platforms. Optimizely customers only
Fewer than 10% of experiments test 4 or more variants, yet those experiments are more than twice as impactful as A/B testsOptimizely, data 2018 to 2023Same data
Only about one third of ideas tested at Microsoft improved the metrics they were designed to improveKohavi et al., "Online Experimentation at Microsoft", 2009Controlled experiments at Microsoft
At Google, about 10% of controlled experiments led to business changesKohavi et al., 2013, quoting Jim ManziManzi's figure as cited in the paper
A Bing ad headline change increased revenue by 12% without hurting key user experience metricsKohavi and Thomke, Harvard Business Review, 2017One controlled experiment, run in 2012

What to do with it: expect most tests to lose, and plan enough tests to find the winners. Size each test before it starts with the A/B test sample size calculator, read it with the statistical significance calculator, and see the complete A/B testing guide.

Reviews, trust and credibility statistics

Reviews and trust statistics show that proof changes buying behavior. Northwestern University's Spiegel Research Center found purchase likelihood for a product with five reviews was 270% greater than for one with none, with a bigger effect on higher-priced products. Stanford research found that a site's design look was the most mentioned factor when people judged credibility.

Reviews, trust and credibility statistics, with sources
StatisticSource and yearWhat it measures
Purchase likelihood for a product with five reviews is 270% greater than for a product with no reviewsSpiegel Research Center, Northwestern University, 2017Purchase likelihood, not sales. Data from PowerReviews, a reviews company
Displaying reviews increased conversion rate 190% for a lower-priced product and 380% for a higher-priced productSpiegel Research Center, 2017Same research
Purchase likelihood typically peaks at average ratings of 4.0 to 4.7, then falls as ratings approach 5.0Spiegel Research Center, 2017Same research
"Verified buyer" badges on reviews improve the odds of purchase by 15%Spiegel Research Center, 2017Same research
The "design look" of a site was mentioned in 46.1% of comments about its credibility, more than any other factorFogg et al., Stanford and Consumer WebWatch, 20022,684 people evaluating live websites. A share of comments, not of people

What to do with it: show real reviews near the buying decision, including some critical ones, and make the site look as careful as your product is. See the guide to trust badges.

How people read pages: usability statistics

Usability research from Nielsen Norman Group explains why clear, scannable pages convert better: people read only a fraction of the words on a page, and a small usability test with five people finds most of a page's usability problems. Both figures are old, and both still describe how visitors behave.

Usability statistics, with sources
StatisticSource and yearWhat it measures
On the average web page, users have time to read at most 28% of the words during a visit; 20% is more likelyJakob Nielsen, Nielsen Norman Group, 2008An upper bound based on time on page, from an analysis of browsing data recorded from 25 users
A test with five participants finds about 85% of usability problemsJakob Nielsen, Nielsen Norman Group, 2000A model estimate. The same article says finding all problems takes at least 15 users, and recommends several small tests over one large one

What to do with it: write for scanning (clear headings, short paragraphs, key facts first), and run small, frequent user tests rather than one big one. See how to reduce cognitive load.

Ecommerce context: how much shopping happens online

E-commerce accounted for 17.1% of total US retail sales in the second quarter of 2026, seasonally adjusted, according to the US Census Bureau's quarterly estimate released on August 18, 2026. That share is the reason small conversion gains on a store add up: a growing share of buying decisions happens on a web page.

Ecommerce share of US retail, with source
StatisticSource and yearWhat it measures
17.1% of total US retail sales were e-commerce in Q2 2026US Census Bureau, Quarterly Retail E-Commerce Sales, released 2026Seasonally adjusted. Estimates are revised with each quarterly release

First-hand data

Convertica's own published test results

Three results from Convertica's own client tests, each with its metric, timeframe and source from the original case study. They are single tests on single sites, not benchmarks, and no result is typical.

Line chart of goal completions from January to April 2018 that steps up after February, labeled "Result: 51.6%+ increase", beside the Empire Flippers logo and the words "Case study: 51.6% increase in lead submissions in 47 days!"

Lead generation

Empire Flippers: a valuation tool submission process rebuilt

A website marketplace's valuation tool asked for a lot of typed input right after the first click. A rebuilt, step-by-step submission process was split-URL tested, then rolled out.

+51.6%

Conversions (valuation tool submissions), 47 days

Source: Empire Flippers, valuation tool submissions, 47 days, split-URL test then rollout

eCommerce

JustThrive: two sequential split tests on a supplement store

A health supplement store wanted more auto-ship subscriptions and a better return on ad spend. Two split tests ran one after the other, the second against the first winner.

+101.82%

Revenue, cumulative across two sequential split tests, 7 December to 24 March

Source: JustThrive, revenue, two sequential split tests, Dec to Mar

Old handwriting in ink on paper, beside the words "Membership eCommerce Case Study: 49.4% increase".

Membership eCommerce

dScryb: more paid membership sign-ups from search results

A membership store showed locked content in its search results with no clear next step. Adding calls to action and access levels to the results was A/B tested on desktop and mobile.

+49.4%

Paid membership sign-ups, 17-day A/B test

Source: dScryb, paid membership sign-ups, 17-day A/B test, 98% confidence

See all CRO case studies

Popular CRO statistics left out, and why

Several CRO statistics that appear on most stats pages are not listed here, because the original could not be opened or does not say what is quoted. Where a figure is widely misquoted, the version in the original source is the one in the tables above.

  • "53% of people leave a mobile site that takes over 3 seconds." Google's original DoubleClick research says 53% of visits are likely to be abandoned if pages take longer than 3 seconds to load, based on aggregated Google Analytics data from mobile sites. It describes visits, not people, and the data is now about a decade old, so it is not in the tables; the newer Google/SOASTA model is.
  • "Reviews increase sales by 270%." The Spiegel Research Center measured purchase likelihood for products with five reviews against none, not sales.
  • "A one second delay costs 7% of conversions." The older report usually credited for this line could not be opened, so it is not listed. Akamai's 2017 release gives a different, sourced figure (a 100 millisecond delay can hurt conversion rates by 7%), which is in the speed table.
  • "75% of people judge a company's credibility by its website design." The Stanford study's published summary reports that design look appeared in 46.1% of credibility comments; the 75% figure was not found in the source opened for this page.
  • Average conversion rates by ad platform or industry from older reports. Many circulating figures come from studies a decade old or more, or from pages that no longer show them, so they are left out.
  • Spending ratios between customer acquisition and conversion. The original reports usually cited for these could not be opened, so the figures are not repeated here.

How to use conversion rate statistics without being misled

Use conversion rate statistics as context for questions, not as targets. An average mixes sites, goals, devices and years that may look nothing like yours. Before acting on any figure, check what was measured, on whose sites, how it was measured, and when. Then measure your own baseline, which is the only number you can actually improve.

  1. Check what counts as a conversion. A landing page median mixes free downloads with sales inquiries.
  2. Check whose data it is. A vendor's report describes its own customers, who may differ from you.
  3. Check the method. A survey answer, a model prediction, an observational study and a controlled experiment are different kinds of evidence.
  4. Check relative vs absolute. "Bounce probability increases 32%" is not "a 32% bounce rate".
  5. Check the year. Old studies can still hold, but devices, browsers and buyer habits change.
  6. Measure yourself. Your conversion rate by page, device and source, over time, is the benchmark that matters. Use the conversion rate calculator, then the CRO checklist to find what to fix.

Questions about CRO statistics

Where do these conversion rate optimization statistics come from?

Every conversion rate optimization statistic on this page comes from the original source: Baymard Institute, Deloitte, Google, Akamai, Unbounce, Optimizely, Microsoft research papers, Harvard Business Review, Northwestern University's Spiegel Research Center, Nielsen Norman Group, Stanford and the US Census Bureau. Each row links to the source and gives its year.

What is the average cart abandonment rate?

Baymard Institute calculates an average documented online shopping cart abandonment rate of 70.22%, based on 50 studies (list last updated September 22, 2025). The studies use different methods and years, so treat it as a broad average rather than a target.

What is the average landing page conversion rate?

Unbounce's 2024 Conversion Benchmark Report puts the median landing page conversion rate across all industries at 6.6%, with industry medians from 3.8% to 12.3%. It covers more than 41,000 landing pages built by Unbounce customers, each counting its own conversion goal.

What percentage of A/B tests win?

Most do not. Optimizely's analysis of over 127,000 experiments run from 2018 to 2023 found that around 12% win on their primary metric. Microsoft researchers reported in 2009 that only about one third of ideas improved the metrics they were designed to improve.

How much does page speed affect conversion rate?

A Google-commissioned Deloitte study (2020) found that a 0.1 second mobile site speed improvement was associated with 8.4% more retail conversions and 10.1% more travel conversions, across 37 brands. It is an observational study, so it shows association, not proof that speed alone caused the change.

Is a 10% conversion rate good?

It depends on what counts as a conversion. For a landing page, 10% is above the 6.6% cross-industry median in Unbounce's 2024 report. For a first-visit purchase on an online store it would be unusually high. Compare against your own past rate on the same traffic before anyone else's.

Why are there fewer statistics here than on other CRO stats pages?

Because a number is only listed when the original source could be opened and the figure found in it. Many widely shared CRO statistics trace back only to other roundups, or the original no longer says what is quoted. Those are left out, and some are explained further down the page.

How often is this page updated?

Figures are checked against their sources when the page is reviewed, and each row shows the year of its source. Some sources update on a schedule: the US Census Bureau publishes quarterly e-commerce estimates, and Baymard updates its abandonment average as new studies appear.

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