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Course Report

[2023] The 250 Most Popular Online Courses of All Time

The best way to choose a free Massive Open Online Course (MOOC) is to choose one that other people have taken and enjoyed.

Most Popular of All Time

The best way to choose a free Massive Open Online Course (MOOC) is to choose one that other people have taken and enjoyed.

Class Central has been maintaining a catalog of these MOOCs ever since they rose to popularity back in 2012. According to Class Central’s 2021 annual report on MOOCs, 220M students have taken at least one course and over 950+ universities have launched 19,400+ courses.

To help learners decide which course to take, Class Central publishes a number of different rankings for best online trainings, including the Best Online Courses of all time based on the tens of thousands of reviews written by Class Central users.

In this ranking, we take a different approach. Instead of ranking courses by reviews, we rank by the number of students who enrolled in the course. In some cases, the best online classes based on reviews are also the courses with the most enrollments. In other cases, courses with large enrollments only have average reviews. This suggests there are popular courses that Class Central’s reviews have missed.

If you are looking for free certificates, check out some of our compilations:

Most Popular Online Courses of All Time

Here’s a quick summary of 250 most popular free online courses of all time, based on the number of enrollments:

  • Enrollments range from 160K to 4.5 million. There are 15 courses with over 1 million enrollments.
  • Together, they account for over 104 million enrollments, with an average of 416K enrollments.
  • Interestingly, almost 40% of the courses are in the field of Business and Humanities.
  • Over 76K reviews have been written on Class Central with an average rating of 4.02.
  • 227 courses are in English, 19 are in Spanish and rest of them are in French, Dutch, and Portuguese.
  • All courses are free to audit. You may need to pay for a certificate.
  • Combined, they represent thousands of hours of content.

Interest in MOOCs and online education has never been greater. If you’re looking for a new online course, take a look at these free courses that millions of students have already taken. Here are the 250 most popular online courses, sorted by number of enrollments:

In addition to this, Class Central also publishes the 100 Most Popular Courses of all time for each year. For these rankings, we only look at courses launched in that year.

Dhawal Shah Profile Image

Dhawal Shah

Dhawal is the CEO of Class Central, the most popular search engine and review site for online courses and MOOCs. He has completed over a dozen MOOCs and has written over 200 articles about the MOOC space, including contributions to TechCrunch, EdSurge, Quartz, and VentureBeat.

Comments 11

  1. Bani

    Thank you so much for sharing all the resources, really helpful and much appreciated.

  2. Suhas

    Thank you for sharing information. It is worth for teachers and students both. Even any person who is interested apart from his acedemic specialization can do it.

  3. Dr.Suvarna Sukhadeo Gund

    Thanks for new information . मराठी माषेसाठी असे कोसऀ आहेत का? नसतील तर आपण यासाठी काय करू शकता? यासाठी मराठी भाषिक म्हणुन मी या कोसऀसाठी प्रयत्न करु शकते.?
    Thanks .

  4. Muvaffak GÖZAYDIN

    What is the meaning of numbers next to name within paranthesis .

    • Suparn Patra

      It is the number of reviews that course has received at Class Central.

  5. Lesa Taylor

    Good morning,
    I see that you are specializing in ed-tech. I am a ed-tech 11 in Maine. I am looking for free courses while i am home this summer. My job at a Boy Scout camp was closed due to COVID 19. Is there any courses for ed-tech to be able to get CEU’S?

    Thank you


  6. David Pérez Diego

    Hello, is there an approximate number of enrollments (historically) for each course? Or some sort of average per year/starting period?

    Thanks for the hard work, amazing data.

  7. Sally Mac

    Wow-this is great! T/you-Sally

  8. Sandipan Debnath

    I really appreciate the efforts put in by the class central team.
    Just a request if it is possible to get the same list separated by subjects so that it becomes easy for us to find specific stream related most popular course.

  9. Alexandros

    I’m finding this article and list a bit disappinting. I’ll share here what I didn’t like in the hope someone will find it helpful and/or I’ll see improvements in the future.

    – The article starts saying that “The *best* way to choose a free Massive Open Online Course (MOOC) is to choose one that other people have taken and enjoyed”, and I think it’s wrong/misleading. 1) even the best courses start with 1 enrollment; 2) the interest of a person in a course and the impact such education will have on her life is not necessarily linked with how many other people have taken and even enjoyed the course; 3) maybe I’m missing something here but, is it enough to consider only how many people have enrolled? Shouldn’t we consider also how many have finished it?

    – The list is too long, incomplete, and disorganised: it’s not possible to filter the list by language, nor by topic; it’s not possible to see how many have enrolled. It’s also strange that some courses that made it to the most-popular courses list have only a handful of reviews… I’d even dare to say that reviews / stars maybe doing more harm than good to the industry: they are not reliable, and they may create positive/negative prejudice in other students. I’d say, NO REVIEWS, present what the course offers and how it compares to other similar ones! Feedback should be gathered with in-depth interviews to satisfied and disappointed students.


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