Online Course Video Statistics

Key takeaways

1. 54.7% of U.S. postsecondary students took at least one distance course in fall 2024, and 26.5% took nothing else. (NCES Digest of Education Statistics) See details
2. Students enrolled exclusively at a distance grew 51.6% between fall 2019 and fall 2024. (NCES; our calculation) See details
3. Coursera learners watched approximately 657.0 million lectures in 2025, up 12% on the year before. (Coursera) See details
4. Udemy counted about 66 learners in its stated audience for every one monthly paying buyer. (Udemy; our calculation) See details
5. Median engagement time was at most 6 minutes across 6.9 million edX video sessions, regardless of video length. (Guo, Kim and Rubin, 2014) See details
6. Among enrolled Stanford students, the mean per-video median share watched was 91.3% — the opposite result. (ASEE, 2015) See details
7. One platform, one year, two correct completion rates: 3.13% of all participants and 46.02% of paid verified-track learners. (The MOOC Pivot) See details
8. 52% of people who registered for a HarvardX or MITx course never entered the courseware at all. (Reich and Ruiperez-Valiente) See details
9. 48% of U.S. faculty taught a fully online course in 2024-25, but online learning officers judged just 28% of faculty fully prepared to design one. (Bay View Analytics; CHLOE 10) See details
10. Udemy cut its instructor revenue share on subscriptions to 15%, effective January 2026. (Udemy 10-K) See details
11. The famous '25-60% retention' claim comes from a 2000 investment-bank paper that put classroom retention at 58%, not 8-10%. (WR Hambrecht + Co, 2000) See details
12. NTL Institute says it can no longer find the original research behind the learning pyramid it is credited with. (NTL Institute) See details

How many people take online courses?

In the United States, 54.7% of all postsecondary students took at least one distance education course in fall 2024, and 26.5% took nothing else, out of total enrollment of 19,659,633. The counts come from table 311.15 of the Digest of Education Statistics, published by the National Center for Education Statistics, which is the only source that counts every degree-granting institution in the country rather than sampling.

The series below is the part worth keeping. Distance enrollment did not appear in 2020 and it did not go back afterwards.

Fall 2020 is the emergency-remote term and should not be read as demand for anything. The useful comparison is 2019 against 2024: the number of students taking no campus courses at all rose 51.6% across those five years, while total enrollment was roughly flat. NCES revises these tables between editions, so a figure quoted from an older Digest will not always match the current one.

Graduate students are the heavier online population. In fall 2024, 3,888,681 undergraduates were enrolled exclusively at a distance against 1,325,644 postbaccalaureate students — but as a share of their own group that is about a quarter of undergraduates and roughly two in five graduate students. A further 1,781,956 exclusively online students were sitting in a different state from the institution teaching them, which is the clearest sign that an online course is not a local product.

Outside the United States, Eurostat's household survey found 34.8% of EU internet users took an online course or used online learning material in 2025, up from 21.4% in 2019. The narrower question — did you take an online course — returns 17.3% of internet users, or 16% of everyone aged 16 to 74. The gap between those numbers is a denominator, not a disagreement, and articles quoting "a third of Europeans take online courses" have taken the broadest reading of the broadest question. India's All India Survey on Higher Education counted 44.0 lakh students in distance mode for 2023-24 and 2.8 lakh in fully online approved programmes — about 4.4 million and 280,000 respectively.

One more U.S. denominator, from the body that administers interstate online delivery: NC-SARA reported 4,442,246 exclusively distance students at participating institutions in fall 2024, and more than 1.7 million students attending an out-of-state institution entirely online in fall 2025.

How big are the online course platforms?

Coursera reported approximately 197 million cumulative registered learners as of 31 December 2025, 54.4 million course enrollments during the year, and — the figure that matters most to anyone editing lessons — approximately 657.0 million lectures watched in 2025, up 12% on the previous year. That works out at 12.1 lectures watched per course enrollment. Its catalogue held more than 13,500 courses from over 375 content creators, sold to more than 1,700 paid enterprise customers.

Udemy's last annual report describes a library of more than 290,000 courses, a stated audience of nearly 84 million learners, more than 1 billion cumulative course enrollments, and an average of 40 million monthly unique visitors. New supply arrives at over 6,300 courses a month, in 78 languages, and instructors collectively earned $168 million in 2025.

Set those learner counts against what people actually pay for. Udemy averaged 1,275 thousand monthly buyers on its consumer marketplace in 2025 — roughly 66 counted learners for every one monthly paying buyer. Neither number is wrong; they answer different questions, and only one of them describes a customer.

Other platforms publish their own counts. Skillsoft served approximately 59 million registered learners with a portfolio of more than 431,000 learning assets, across over 3,000 enterprise customers. Docebo's platform was used by nearly 3,500 companies. Duolingo reported more than 130 million monthly active users. Khan Academy, a nonprofit that publishes an annual report, recorded 189.6 M registered users, 104.9 M yearly active learners and 66.8 B learning minutes across 842 courses in school year 2024-25. Registered Moodle sites reported 59,195,241 courses and 3,647,757,049 course enrolments in a snapshot taken on 14 September 2026; that is a live counter and it moves daily. MIT OpenCourseWare publishes materials from over 2,500 MIT courses and its YouTube channel has over 6 million subscribers. LinkedIn states that about ~123 hours of learning content are consumed on its platform every minute, and edX states on its own site that 100M learners use it. Thinkific says its customers have earned $4.23B selling courses; that is a platform marketing claim with no date attached, and it is gross, not take-home.

The more important fact about this section is that it is getting harder to write. Coursera completed its acquisition of Udemy on 11 May 2026; Udemy was delisted the same day and deregistered on 21 May 2026, so the fiscal 2025 annual report cited above is the last one that will ever exist. Coursera's own quarterly report for the period ended 30 June 2026 no longer carries a registered-learner metric at all. 2U, which owned edX, filed for Chapter 11 in 2024 and deregistered; Instructure was taken private; Chegg has stopped disclosing subscriber counts. Class Central's annual MOOC census appears to have stopped after its 2021 edition. Several widely quoted platform numbers are now frozen at whatever the last filing said, and no newer audited figure is coming.

How long should an online course video be?

There is no research finding that names a best length. What exists is a set of platform rules, a set of platform recommendations, and one well-known 2013 measurement of how long students keep watching — which is not the same question. Take them in that order.

The rules are hard numbers and they are published by the platforms themselves. Udemy will not publish a paid course with less than 30 minutes of video or fewer than 5 separate lectures, requires 720p or 1080p at a 16:9 ratio, and caps free courses at under 2 hours. Skillshare requires a class of at least 10 minutes, describes its typical class as 20 to 60 minutes split into 2- to 8-minute lessons, and allows short-form classes from 2 minutes up to 15.

Two of those are recommendations rather than rules, and one of them carries a number worth flagging: Coursera states that keeping lectures under ten minutes raises a course's completion rate by 16%. Coursera sells course hosting, so that is a platform's claim about its own product and it publishes no method alongside it.

Now the measurement everyone cites. Across 6.9 million video watching sessions on edX, median engagement time was 6 minutes at most, regardless of how long the video actually ran. The dataset was 6,902,358 sessions across 862 videos and 127,839 students in four Fall 2012 maths and science courses. Engagement fell as videos lengthened: for the shortest videos, 75% of sessions ran past three quarters of the way through, and 56% of sessions were followed by an attempt at the assessment that came next, against 31% for the longest. Students engaged with tutorial videos for only 2 to 3 minutes.

A companion second-by-second analysis of the same 862 videos found that about 55.2% of viewing sessions ended before the video did, rising to 78.6% among students re-watching, and 61.3% for tutorials against lectures. Its regression predicted a 71% dropout rate for a twenty-minute video against 53% for a five-minute one.

Then the finding that almost never gets quoted alongside it. When Stanford researchers measured enrolled, fee-paying students rather than open registrants, the numbers inverted. Across 13,107 watching sessions of 28 videos from an introductory computer science course, median watching time was 12.1 minutes on lectures running 50 minutes — and once a student's repeat visits to one video were stitched together, the mean of the per-video median share watched was 91.3%. Most students watched either almost all of a video or almost none of it. Short videos hold open-registration audiences; they are not a universal law of attention.

Two vendors publish length-versus-engagement benchmarks from their own hosting data. Wistia reports a 52% average engagement rate for videos under a minute, over 50% watched for educational and tutorial videos in the one-to-five-minute band, and an 11% drop once a video passes thirty minutes. Vidyard reports 65% of viewers staying to the end under one minute against 20% past twenty minutes. Both companies sell video hosting, both measure their own customers' libraries rather than course platforms, and neither publishes a sample frame.

Three different quantities are moving through that evidence and roundups routinely blend them: engagement time is how long a session lasts, dropout is whether a session reaches the end, and watch percentage is how much of the runtime is consumed. A claim about one is not a claim about the others.

Do people finish online courses?

There is no single completion rate for online courses, and the spread between the published figures is caused almost entirely by who is counted in the denominator. In 2017-18, 3.13% of HarvardX and MITx course participants completed their course. In the same year, on the same platform, 46.02% of learners who had paid to enter the verified track completed theirs. That is a factor of 14.7 between two correct numbers.

The reason the low numbers are so low is that registration on an open platform costs nothing. Across six years of HarvardX and MITx courses, 52% of people who registered never entered the courseware at all, out of 12.67 million registrations. Harvard and MIT exclude 1.3 million such registrations from their own published rates before calculating anything, counting as a participant only someone who opened at least one chapter. A completion percentage that includes people who never arrived is measuring the price of the sign-up button.

The first-year numbers show the shape clearly: 841,687 registrations produced 292,852 registrants who never engaged with any content, 35,937 who explored half or more of a course, and 43,196 certificates. By year two the sample was 1.47 million participants and the certification rate was 8%. Over four years the two universities recorded 4.5 million participants and 245 thousand certificates.

Attrition is front-loaded and it is mostly a first-week phenomenon. Around 50% of registrants stopped being active within the first week, and the review of 221 MOOCs found the first two weeks to be the critical window, after which weekly losses settle at about 3%. Engagement and certification are also not the same thing: 44% of learners who explored half or more of a HarvardX or MITx course went on to certify, so most deeply engaged learners never appear in a completion statistic at all. Certification rates were 14% in the humanities against 7% in computer science. In the largest single cohort, only 12% of 1.1 million unique learners went on to take a second course.

Enrollment on open platforms is also not the same commitment as enrolling at a university, which is the comparison people reach for. 61.1 percent of U.S. students who started postsecondary education in fall 2019 completed a credential within six years, falling to 34.1% for those who began part-time; NCES puts the six-year bachelor's graduation rate at 64 percent and first-year retention at 82 percent. 43.1 million U.S. adults hold some college credit and no credential. Formal education does not have a completion problem that online courses uniquely lack, nor the reverse — the two are counted differently.

One thing neither large platform discloses: neither Coursera's nor Udemy's annual report states a completion rate, completions per learner, or any persistence metric. Coursera publishes 197 million cumulative registered learners against 54.4 million course enrollments in a year and 657.0 million lectures watched, and stops there. Any per-platform completion figure in circulation is somebody's estimate.

Who makes online course video, and are they ready to?

In the United States the supply side is large and mostly institutional. There were 3,896 degree-granting postsecondary institutions in 2022-23, of which 1,599 were public and 683 private for-profit, employing 1,530,513 faculty in fall 2023 — 670,688 of them part-time. Average salary for full-time instructional faculty on nine-month contracts was $101,925 in 2023-24.

Roughly half of them teach online. Bay View Analytics found 48% of faculty taught at least one fully online course in 2024-25, against 72% teaching at least one face-to-face course and 23% teaching blended; 65% taught in a single modality only. The survey ran in April 2025 with 3,447 faculty responding and is published under an open licence with its method attached.

Readiness is the gap. Chief online learning officers surveyed for CHLOE 10 judged only 28% of their faculty fully prepared for online course design and 45% fully prepared for online teaching. Institutional intent nevertheless points one way: 88% plan to expand online offerings within three years and 74% report rising interest from graduate students, even as the share offering online-specific student orientations fell to 83% from 93% in 2021.

Instructor preference is moving the other way, and it is worth stating plainly because it cuts against the institutional plans above. Tyton Partners found the share of instructors preferring to teach face-to-face rose to 64% in 2025 from 55% in 2023, with the face-to-face share of courses rising to 72% from 56%. In the UK, Jisc found 64% of higher education teaching staff rated their digital teaching environment positively and 53% rated institutional support above average, but only 10% had any formal recognition for digital teaching skills.

Two production details from the edX corpus are useful to anyone cutting lessons: instructors spoke at a mean of 156 wpm, ranging from 48 to 254, and 89% of the videos studied were ordinary lectures or tutorials rather than any more elaborate format.

What is the money in online course video?

Two platforms carry most of the public financial record, and both filed for fiscal 2025. Coursera reported total revenue of $757.5 million, split $502.2 million consumer and $255.3 million enterprise, at a 54.6% gross margin. It paid $271.1 million in segment content costs to the universities and companies supplying its catalogue — 35.8% of total revenue — equal to 38.6% of consumer segment revenue. Udemy reported total revenue of $789.8 million, split $524.1 million enterprise and $265.8 million consumer, at a 66% gross margin, with content costs at 32% of consumer segment revenue.

The instructor share is the number that is actually moving. Udemy cut the instructor revenue share on its subscription offerings to 15% effective 1 January 2026, the third step of a documented reduction from 20% through 17.5%. Coursera, separately, disclosed that it has met opposition to its content fee terms. Anyone building a business on course video for a marketplace should read both filings rather than either one.

Elsewhere in the sector the direction is down. Chegg's net revenues fell to $376.9 million in 2025 from $617.6 million in 2024 and $716.3 million in 2023. Skillsoft reported $512.7 million for the twelve months to 31 January 2026, a third consecutive decline, and spent $20.3 million on proprietary content development, down year over year. Docebo, which sells to employers rather than learners, grew: annual recurring revenue of $238.1 million with an average contract value of $66,500 per customer.

Employer training budgets, the other buyer of course video, are not expanding either. The UK Department for Education's employer survey puts total training spend at £53.0 billion in the year to 2024, equivalent to £2,710 per person trained and £1,700 per employee — a series low on all three measures. Eurostat's continuing vocational training survey put the cost at 1 441 PPS per participant and 64 euros per training hour in 2020. On the creator side, Hotmart, which owns Teachable, announced in March 2024 that creators on its platforms had cumulatively earned $10 billion; that is gross revenue across all product types, announced by the platform, not instructor take-home from courses.

What the popular online course numbers really say

Four statistics do most of the work in articles about course video. Each one is repeated with a confident attribution, and each attribution is wrong in a way that changes what the number means. They are traced here to the earliest document we could date.

"The optimal course video is under six minutes"

The earliest datable document is a November 2013 post on the edX blog by Philip Guo, the researcher who ran the analysis, stating that the optimal video length is 6 minutes or shorter and that average engagement time maxed out at 6 minutes regardless of how long the video ran. Those two sentences sit in the same paragraph, and they do not agree: a ceiling on how long people watch is not an optimum, and nothing in the study compared a six-minute video against a five- or seven-minute one on any outcome.

The peer-reviewed version, published four months later, reports the same result as a median engagement time and is explicit about its limits. Its authors write that it is important not to draw any conclusions about student learning from findings about video engagement. The paper also records that edX staff were already recommending videos of less than 6 minutes before the data existed, based on their prior intuitions — the rule predates the evidence now used to justify it.

What to use instead: median engagement time was at most six minutes across 6.9 million sessions in four Fall 2012 maths and science courses on one platform, and it describes watching, not learning. The Stanford measurement of enrolled students in the section above found median watch times of twelve minutes and per-video median watch shares above 90%, so the six-minute ceiling is a property of open-registration audiences rather than of human attention.

"Online learners retain 25 to 60% more, against 8 to 10% in a classroom"

This is the most-cited claim in e-learning marketing and it is wrong twice over at its own source. The earliest datable document is a March 2000 equity research white paper, Corporate e-Learning: Exploring a New Frontier, written by two investment analysts at WR Hambrecht + Co. Its actual sentence puts average content retention for an instructor-led class at 58% and says online learning enhances the retention rate by 25 – 60%.

So the classroom baseline in the origin document is 58%, not 8 to 10%, and the 25-60% figure is a relative lift, not an absolute retention rate. The two halves of the popular claim are not even measuring the same thing. The "8 to 10%" figure appears nowhere in the document it is attributed to, and we could not locate any originating source for it.

The Research Institute of America, credited almost everywhere as the author of this research, did not produce it. The white paper credits that firm only with a forgetting-curve claim, and cites three other works for it. The publisher was an investment bank that made a market in the securities of e-learning companies profiled in the same report. A 2019 investigation that chased the claim to its source concluded the supposedly recent research was at least 20 years old.

What to use instead: nothing. There is no sound measurement of comparative retention behind this claim.

The learning pyramid: "people remember 10% of what they read, 90% of what they do"

The numbers are usually credited to the NTL Institute. NTL's own form letter to enquirers gives the figures, beginning with 10% for reading, and claims they were developed at its Bethel, Maine campus in the early sixties. The same letter concedes that NTL no longer has, and cannot find, the original research supporting them.

They are also much older than that claim. The percentages appear in print as far back as 1914, presented even then as long-established. A 2018 peer-reviewed analysis found versions circulating for more than 160 years and concluded the models did not originate from empirical research; a 2014 peer-reviewed review concluded the retention chart cannot be supported in terms of scientific validity or logical interpretability. Edgar Dale's Cone of Experience, frequently shown with the percentages attached, carried no numbers at all in any edition.

What to use instead: nothing.

"Only 3% of people finish an online course"

Both the very low and the moderately low versions are real numbers with different denominators, as the completion section sets out. The figure usually quoted as "about 15%" comes from Katy Jordan's public MOOC dataset, which she compiled from news stories and blog posts rather than platform data, and which reports 15%. Her peer-reviewed research note on the same work gives the defensible version: a median of 12.6% across 221 MOOCs, with a range from 0.7% to 52.1%. That dataset has not been updated since 2015.

The Harvard and MIT figures show why one course produces three headlines. In a typical course across four years, 7,900 people accessed some content after registering while 500 certified. A six-year analysis of the same platform found completion rates had not improved across 6 years. All of these describe free registrations, which is the whole story.

What to use instead: the median of 12.6% across 221 MOOCs, always stated with its denominator.

"The human attention span is eight seconds"

This one is borrowed from elsewhere to justify short lessons. The BBC traced it to a 2015 Microsoft Canada report that did not conduct the research but cited a statistics website, whose own listed sources had no record of it; the Microsoft document drew on a survey of 2,000 people for its other findings. Attention researchers quoted in the same investigation say an average attention span is not a measurable quantity, because attention depends on the task. There is also no evidence that goldfish have short attention spans.

What to use instead: nothing. If a lesson needs to be shorter, the reason is the structure of the material, not a number about goldfish.

"The global e-learning market will be worth $X billion"

Every version of this figure traces to a market-research reseller rather than to any statistical agency, filing or survey owner, and the resellers do not agree with one another. For the same market in the same base year, the published estimates we found differ by more than threefold, and the ten-year projections by roughly eightfold. One figure in wide circulation is not a market size at all — it is a projected increase, requoted as a total. None of the firms publishes a method that can be checked.

No figure from those sources appears anywhere on this page, and none is reproduced here. Where a real denominator is needed, the filings and government series above supply one.

How we built this page

We started from the questions people search for about online course video statistics and looked for the organization that actually produced each answer. Every figure on this page sits in an evidence ledger with its source, the exact table or paragraph it came from, the measurement period, the population measured, and the date we checked it. This edition holds 184 figures from 51 publishers.

On September 22, 2026, every figure was re-fetched from its source on a cleared cache and matched against the recorded wording; 203 of the 207 sourced rows re-verified automatically, with no failures. Sources that refuse automated requests — Udemy, Skillshare, Thinkific and Coursera help documentation, and the 2013 edX blog post, all behind Cloudflare or since removed — were read from dated Internet Archive captures of the publisher's own pages, recorded as such in the evidence table. Four U.S. Bureau of Labor Statistics wage and employment figures were collected but are not published here: the public data API's daily request quota was exhausted before they could be independently re-checked on publication day, and we do not print a figure we could not verify ourselves. EDUCAUSE research, the ATD State of the Industry report and the paywalled journal version of The MOOC Pivot were left out or routed to an openly published copy rather than obtained another way.

We only cite the producer: government agencies, regulators, company filings and official posts, and the survey owner's own report. We do not cite statistics roundups, Statista-style aggregators, or salary sites without a public method. We did not bypass paywalls or sign-up forms; where a full report was gated, we used only the figures its publisher states publicly.

Figures marked "our calculation" are arithmetic on the cited numbers, and anyone can reproduce them:

This edition contains no Mark Studios customer data.

Limitations

• Most engagement research comes from one platform and one era. The video-length findings quoted everywhere, and repeated here, are drawn from four Fall 2012 maths and science courses on edX. They do not describe humanities courses, corporate training, or paying students, and the page says so where it uses them.
• Open-platform enrollment is not a commitment. Registration is free, so completion percentages calculated against registrations are measuring sign-up friction as much as learning. Every completion figure here is labelled with its denominator.
• Vendor benchmarks are vendor benchmarks. Wistia, Vidyard, Coursera and Thinkific figures come from companies selling video hosting or course platforms, measuring their own customers, usually without a published sample frame. Each is labelled.
• Platform counts are shrinking as a public record. Udemy was acquired and deregistered in May 2026, 2U and Instructure no longer file, Coursera has dropped its registered-learner metric, and Chegg has dropped subscriber counts. Several figures here are final disclosures that will not be updated.
• Live counters drift. The Moodle totals are a dated snapshot taken on 14 September 2026, not a stable figure.
• No market-size estimate appears on this page. Every version we found traces to a market-research reseller with no checkable method, and the published estimates for the same year differ by more than threefold.

How to cite this page

For a single figure, cite the original publisher named next to it, and link here if the verification trail is useful to your readers. Each figure has its own anchor, so you can link straight to it, for example https://www.markstudios.com/research/online-course-video-statistics#ORG-007. To cite the page as a whole:

Mark Studios. "Online Course Video Statistics." Last verified Sep 22, 2026. https://www.markstudios.com/research/online-course-video-statistics

Our calculations and the evidence table are free to reuse with attribution and a link to this page. Each underlying figure remains the claim of its original publisher, and some publishers ask for a link when their figures are reused.

Sources

Download the evidence table (CSV)

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• Sep 22, 2026: First published with 184 figures from 51 publishers, each checked against its original source.