Last week, Class Central published a list of Udemy’s 250 most popular online courses, noting that they had over 157,000 courses, 425 million enrollments, and 32 million ratings. Surprisingly, despite its magnitude, Udemy’s catalog seems to have seldom been analyzed.
So in this article, we’re going to break down Udemy’s numbers a little further. My colleague @Suparn collected data about the provider’s catalog. And with my newly acquired Excel skills (albeit rudimentary), I dug into the data. Here’s what I found.
Udemy By the Numbers
Half of Udemy’s courses belong to the fields of Business and Technology, but they account for 70% of all enrollments.
Technology courses are the most popular. They have on average 4,200 learners per course, well above the 2,700 average across the platform.
The average course length is 4.5 hours, while the median is 2 hours. As course lengths increase, average enrollments also increase: learners gravitate towards longer courses.
Courses that are less than 1 hour long have an average enrollment of 2,100, while courses 15–20 hours long have an average enrollment of 7,300. There are 4,000 courses longer than 20 hours — their average enrollment is 11,400.
90% of Udemy courses are paid. Course prices range from $19.99 to $199.99 (without any discounts or deals).
As you can see below, average enrollments increase as the courses’ list prices increase. This doesn’t seem to conform to the traditional supply-demand pattern: higher prices resulting in lower enrollments. This is because Udemy courses are rarely sold at list price.
Udemy runs a lot of promotions bringing the cost of the courses down. Popular courses probably have increased their list price. I’ve noticed over the last couple of years that the frequency of these promotions has gone down.
40% of Udemy’s courses cost less than $30, while 24% cost more than $100.
Udemy courses are available in 70 different languages. 63% of all courses are offered in English. Here are the five most common languages on the platform:
English — 63%.
Portuguese — 9%.
Spanish — 8%.
Turkish — 3.3%.
French & Japanese — 2.4%.
Combined, Udemy’s 157K courses have gathered ~425 million enrollments and average 2,700 enrollments per course. What I found most surprising is that the median enrollment is only 188, which means that half of Udemy’s courses don’t reach 200 learners.
Currently, there are 335 courses with over 100K enrollments and a couple with over a million enrollments.
Do Udemy courses satisfy the Pareto 80/20 principle? I found that Udemy’s top-20% courses by enrollment account for 90% of all enrollments.
In total, Udemy courses have received 32 million ratings. Class Central’s analysis found that 21K of Udemy’s 157K courses have no rating at all.
Ratings tend to be heavily skewed towards the positive side. 85% of the ratings are 4–5 stars. 1–2 star represent only ~4% of all the ratings.
We also noticed that the rating is correlated with the length of the course. Longer courses might just be higher effort, more polished, or appear to offer more bang for your buck when offered at a discount.
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