The Report by Class Central

Disclosure: Class Central is learner-supported. When you buy through links on our site, we may earn an affiliate commission.

Course Report

[2021] 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 2020 annual report on MOOCs, 180M students have taken at least one course and over 950+ universities have launched 16,300+ courses.

To help learners decide which course to take, Class Central publishes a number of different rankings 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 top reviewed courses 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.

By The Numbers

The top 250 most popular online courses of all time combined represent 100 million enrollments. The first 11 courses in the list below each have over a 1 million enrollments. Coursera co-founder Andrew Ng’s Machine Learning course is the most popular course of all time with over 4 million enrollments.

The average enrollment for the the Top 250 is at 390k  and the median at 265k.

250 Most Popular Online Courses of All Time

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.

  1. Machine Learning from Stanford University ★★★★★(374)
  2. The Science of Well-Being from Yale University ★★★★★(22)
  3. Learning How to Learn: Powerful mental tools to help you master tough subjects from University of California, San Diego ★★★★★(18011)
  4. CS50’s Introduction to Computer Science from Harvard University ★★★★★(103)
  5. Programming for Everybody (Getting Started with Python) from University of Michigan ★★★★★(28330)
  6. Introduction to Computer Science and Programming Using Python from Massachusetts Institute of Technology ★★★★☆(126)
  7. English for Career Development from University of Pennsylvania ★★★★☆(23)
  8. IELTS Academic Test Preparation from University of Queensland ★★★★★(4)
  9. COVID-19 Contact Tracing from Johns Hopkins University ★★★★★(11)
  10. TOEFL® Test Preparation: The Insider’s Guide from ETS ★★★★★(6)
  11. Successful Negotiation: Essential Strategies and Skills from University of Michigan ★★★★★(15)
  12. Neural Networks and Deep Learning from deeplearning.ai ★★★★★(15)
  13. Chinese for Beginners from Peking University ★★★★☆(44)
  14. Financial Markets from Yale University ★★★★☆(33)
  15. Analyzing and Visualizing Data with Excel from Microsoft ★★★★☆(13)
  16. CS50’s Web Programming with Python and JavaScript from Harvard University ★★★★★(11)
  17. First Step Korean from Yonsei University ★★★★★(35)
  18. Algorithms, Part I from Princeton University ★★★★★(59)
  19. Python Data Structures from University of Michigan ★★★★★(11082)
  20. Speak English Professionally: In Person, Online & On the Phone from Georgia Institute of Technology ★★★★☆(6)
  21. Technical Support Fundamentals from Google ★★★☆☆(7)
  22. English Grammar and Style from University of Queensland ★★★★☆(32)
  23. Introduction to Linux from Linux Foundation ★★★★☆(38)
  24. Write Professional Emails in English from Georgia Institute of Technology ★★★☆☆(3)
  25. Entrepreneurship in Emerging Economies from Harvard University ★★★★★(10)
  26. AI For Everyone from deeplearning.ai ★★★★★(6)
  27. The Data Scientist’s Toolbox from Johns Hopkins University ★★★☆☆(165)
  28. Introduction to Psychology from Yale University ★★★★★(12)
  29. Data Science: R Basics from Harvard University ★★★★★(10)
  30. R Programming from Johns Hopkins University ★★★☆☆(245)
  31. Grammar and Punctuation from University of California, Irvine ★★★★☆(33)
  32. Introduction to Data Science in Python from University of Michigan ★★☆☆☆(46)
  33. Excel Skills for Business: Essentials from Macquarie University ★★★★☆(5)
  34. Stanford Introduction to Food and Health from Stanford University ★★★★☆(42)
  35. English for the Workplace from British Council ★★★★★(1136)
  36. Buddhism and Modern Psychology from Princeton University ★★★★★(29)
  37. HTML, CSS, and Javascript for Web Developers from Johns Hopkins University ★★★★★(17)
  38. The Science of Happiness from University of California, Berkeley ★★★★★(32)
  39. Introduction to Philosophy from University of Edinburgh ★★★★☆(72)
  40. Bitcoin and Cryptocurrency Technologies from Princeton University ★★★★☆(23)
  41. Fundamentals of Graphic Design from California Institute of the Arts ★★★★☆(18)
  42. Using Python to Access Web Data from University of Michigan ★★★★★(3996)
  43. Marketing in a Digital World from University of Illinois at Urbana-Champaign ★★★★★(169)
  44. Google Cloud Platform Fundamentals: Core Infrastructure from Google ★★★★☆(5)
  45. Basic English 1: Elementary from King’s College London ★★★★☆(4)
  46. Contract Law: From Trust to Promise to Contract from Harvard University ★★★★★(13)
  47. The Architectural Imagination from Harvard University ★★★★☆(11)
  48. Basic Spanish 1: Getting Started from Universitat Politècnica de València ★★★★☆(319)
  49. Justice from Harvard University ★★★★★(45)
  50. What is Data Science? from IBM ★★★☆☆(2)
  51. Fundamentals of Neuroscience, Part 1: The Electrical Properties of the Neuron from Harvard University ★★★★★(19)
  52. Child Nutrition and Cooking from Stanford University ★★★★☆(31)
  53. Finanzas personales from Universidad Nacional Autónoma de México
  54. Rhetoric: The Art of Persuasive Writing and Public Speaking from Harvard University ★★★★☆(4)
  55. Social Psychology from Wesleyan University ★★★★★(82)
  56. Programming Foundations with JavaScript, HTML and CSS from Duke University ★★★★☆(11)
  57. A Life of Happiness and Fulfillment from Indian School of Business ★★★★★(492)
  58. Introduction to HTML5 from University of Michigan ★★★★☆(46)
  59. CS50’s Introduction to Game Development from Harvard University ★★★★★(2)
  60. Improving Deep Neural Networks: Hyperparameter Tuning, Regularization and Optimization from deeplearning.ai ★★★★★(3)
  61. Programming for Everybody (Getting Started with Python) from University of Michigan
  62. Introduction to Programming with MATLAB from Vanderbilt University ★★★★★(207)
  63. Modern Art & Ideas from The Museum of Modern Art ★★★★★(5)
  64. Work Smarter, Not Harder: Time Management for Personal & Professional Productivity from University of California, Irvine ★★★★☆(42)
  65. Seeing Through Photographs from The Museum of Modern Art ★★★★☆(4)
  66. Primeros Auxilios Psicológicos (PAP) from Universitat Autònoma de Barcelona (Autonomous University of Barcelona) ★★★★★(1)
  67. Algorithmic Toolbox from University of California, San Diego ★★★★☆(23)
  68. Financial Engineering and Risk Management Part I from Columbia University ★★★★☆(12)
  69. Mindfulness for Wellbeing and Peak Performance from Monash University ★★★★★(204)
  70. Using Databases with Python from University of Michigan ★★★★★(3140)
  71. Convolutional Neural Networks from deeplearning.ai ★★★★★(8)
  72. Competitive Strategy from Ludwig-Maximilians-Universität München ★★★★★(22)
  73. Start Writing Fiction from The Open University ★★★★☆(21)
  74. Introduction to Negotiation: A Strategic Playbook for Becoming a Principled and Persuasive Negotiator from Yale University ★★★★★(13)
  75. HTML5 and CSS Fundamentals from World Wide Web Consortium (W3C) ★★★★☆(6)
  76. Academic and Business Writing from University of California, Berkeley ★★★★☆(14)
  77. Introductory Human Physiology from Duke University ★★★★☆(28)
  78. Psychological First Aid from Johns Hopkins University ★★★★☆(46)
  79. Introduction to Project Management from University of Adelaide ★★★★☆(6)
  80. Introduction to Psychology from University of Toronto ★★★★★(25)
  81. Initiating and Planning Projects from University of California, Irvine ★★★★☆(19)
  82. Project Management: The Basics for Success from University of California, Irvine ★★★★☆(25)
  83. Statistics and R from Harvard University ★★★★☆(20)
  84. Design Thinking for Innovation from University of Virginia ★★★★★(4)
  85. Introduction to Java Programming: Starting to code in Java from Universidad Carlos iii de Madrid ★★★★☆(7)
  86. Mindshift: Break Through Obstacles to Learning and Discover Your Hidden Potential from McMaster University ★★★★★(6221)
  87. A Beginner’s Guide to Writing in English for University Study from University of Reading ★★★★☆(22)
  88. Introduction to Mathematical Thinking from Stanford University ★★★★☆(51)
  89. Machine Learning Foundations: A Case Study Approach from University of Washington ★★★★☆(40)
  90. Introduction to C++ from Microsoft ★★★★☆(7)
  91. Contabilidad para no contadores from Universidad Nacional Autónoma de México
  92. Excel: Fundamentos y herramientas from Universitat Politècnica de València ★★★★★(453)
  93. Structuring Machine Learning Projects from deeplearning.ai ★★★★★(3)
  94. How to Write an Essay from University of California, Berkeley ★★★★☆(26)
  95. CS50’s Introduction to Artificial Intelligence with Python from Harvard University ★★★★★(1)
  96. Crash Course on Python from Google
  97. Game Theory from Stanford University ★★★★☆(34)
  98. The Science of Everyday Thinking from University of Queensland ★★★★★(48)
  99. Gestión de Proyectos de Desarrollo from IDB ( Inter-American Development Bank ) ★★★★☆(2)
  100. Data Science: Machine Learning from Harvard University ★★★★☆(4)
  101. Mechanical Ventilation for COVID-19 from Harvard University ★★★★★(23)
  102. Mastering Data Analysis in Excel from Duke University ★★☆☆☆(26)
  103. Python Basics for Data Science from IBM ★★☆☆☆(3)
  104. Conversational English Skills | 生活英语听说 from Tsinghua University ★★★★☆(12)
  105. Étudier en France: French Intermediate course B1-B2 from École Polytechnique ★★★★★(4)
  106. Cryptography I from Stanford University ★★★★★(53)
  107. English for Business and Entrepreneurship from University of Pennsylvania ★★★★★(7)
  108. SQL for Data Science from University of California, Davis ★★★★☆(3)
  109. CS50’s Mobile App Development with React Native from Harvard University ★★★★☆(1)
  110. English Composition I from Duke University ★★★☆☆(19)
  111. Introduction to Cyber Security from The Open University ★★★★☆(21)
  112. The Bits and Bytes of Computer Networking from Google ★★★★★(2)
  113. Sequence Models from deeplearning.ai ★★★★★(4)
  114. Python for Data Science, AI & Development from IBM ★★★☆☆(2)
  115. Build Your First Android App (Project-Centered Course) from École Centrale Paris ★★★★☆(5)
  116. Basic English 2: Pre-Intermediate from King’s College London ★★★★★(3)
  117. Aprendiendo a aprender: Poderosas herramientas mentales con las que podrás dominar temas difíciles (Learning How to Learn) from University of California, San Diego ★★★★★(7)
  118. Teaching English Online from Cambridge English Language Assessment ★★★★★(2)
  119. Python for Data Science from University of California, San Diego ★★★★☆(47)
  120. Using Python for Research from Harvard University ★★★★☆(12)
  121. Principles of Biochemistry from Harvard University ★★★★★(12)
  122. Artificial Intelligence (AI) from Columbia University ★★★★☆(12)
  123. Introduction to Java Programming – Part 1 from The Hong Kong University of Science and Technology ★★★☆☆(6)
  124. Introduction to Marketing from University of Pennsylvania ★★★★☆(73)
  125. Think Again I: How to Understand Arguments from Duke University ★★★★☆(11)
  126. Guitar for Beginners from Berklee College of Music ★★★★★(21)
  127. Understanding Language: Learning and Teaching from University of Southampton ★★★★☆(7)
  128. Marketing Analytics from University of Virginia ★★★★☆(12)
  129. Java Programming: Solving Problems with Software from Duke University ★★★☆☆(15)
  130. Learn to Speak Korean 1 from Yonsei University ★★★★★(11)
  131. How to Succeed at: Interviews from The University of Sheffield ★★★★★(374)
  132. Camino a la Excelencia en Gestión de Proyectos from Pontificia Universidad Católica de Chile
  133. Data Science Math Skills from Duke University ★★★★☆(10)
  134. Introduction to Big Data from University of California, San Diego ★★★☆☆(35)
  135. Science of Exercise from University of Colorado Boulder ★★★★★(4)
  136. Introduction to the Internet of Things and Embedded Systems from University of California, Irvine ★★★★☆(12)
  137. How to Succeed at: Writing Applications from The University of Sheffield ★★★★★(358)
  138. Leaders of Learning from Harvard University ★★★★☆(25)
  139. Positive Psychology from The University of North Carolina at Chapel Hill ★★★★☆(28)
  140. HTML5 Coding Essentials and Best Practices from World Wide Web Consortium (W3C) ★★★★☆(12)
  141. Introduction to TensorFlow for Artificial Intelligence, Machine Learning, and Deep Learning from deeplearning.ai ★★★★★(1)
  142. Vital Signs: Understanding What the Body Is Telling Us from University of Pennsylvania ★★★★★(48)
  143. Python Basics from University of Michigan ★★★★☆(1)
  144. Learn to Program in Java from Microsoft ★★★★★(3)
  145. Querying Data with Transact-SQL from Microsoft ★★★★☆(4)
  146. Fundamentos de Excel para Negocios from Universidad Austral ★★★★★(1)
  147. Fundamentals of Music Theory from University of Edinburgh ★★★★☆(23)
  148. Mathematics for Machine Learning: Linear Algebra from Imperial College London ★★★☆☆(7)
  149. Business Metrics for Data-Driven Companies from Duke University ★★★★☆(8)
  150. AWS Fundamentals: Going Cloud-Native from Amazon Web Services
  151. Aprender from Universidad Nacional Autónoma de México ★★★★★(107)
  152. Supply Chain Fundamentals from Massachusetts Institute of Technology ★★★★★(14)
  153. Fashion as Design from The Museum of Modern Art ★★★★☆(3)
  154. Introduction to Dutch from University of Groningen ★★★★★(236)
  155. Introduction to Financial Accounting from University of Pennsylvania ★★★★★(63)
  156. Child Protection: Children’s Rights in Theory and Practice from Harvard University ★★★★★(3)
  157. Object Oriented Programming in Java from University of California, San Diego ★★★★★(15)
  158. Learn to Program: The Fundamentals from University of Toronto ★★★★★(108)
  159. An Introduction to Screenwriting from University of East Anglia ★★★★★(3)
  160. Medical Neuroscience from Duke University ★★★★★(46)
  161. Applied Machine Learning in Python from University of Michigan ★★★★☆(6)
  162. Indigenous Canada from University of Alberta ★★★★☆(8)
  163. Basic Statistics from University of Amsterdam ★★★★☆(11)
  164. Probability – The Science of Uncertainty and Data from Massachusetts Institute of Technology ★★★★★(32)
  165. Algorithms, Part II from Princeton University ★★★★★(21)
  166. Programming Basics from Indian Institute of Technology Bombay ★★☆☆☆(16)
  167. Becoming a Successful Leader (Inclusive Leadership Training)
  168. Robótica from Universidad Nacional Autónoma de México ★★☆☆☆(2)
  169. Introduction to Probability and Data with R from Duke University ★★★★☆(6)
  170. English in Early Childhood: Language Learning and Development from British Council ★★★★★(1226)
  171. Álgebra básica from Universidad Nacional Autónoma de México
  172. Nutrition and Health: Macronutrients and Overnutrition from Wageningen University ★★★★★(232)
  173. Food as Medicine from Monash University ★★★★★(110)
  174. Writing in the Sciences from Stanford University ★★★★★(9)
  175. Introduction to Personal Branding from University of Virginia ★★★★☆(15)
  176. Italian Language and Culture: Beginner (2021-2022) from Wellesley College ★★★★☆(3)
  177. Supply Chain Analytics from Massachusetts Institute of Technology ★★★☆☆(3)
  178. How Things Work: An Introduction to Physics from University of Virginia ★★★★★(27)
  179. Customer Analytics from University of Pennsylvania ★★★☆☆(16)
  180. C++ For C Programmers, Part A from University of California, Santa Cruz ★★★☆☆(25)
  181. Cameras, Exposure, and Photography from Michigan State University ★★★★☆(6)
  182. A Hands-on Introduction to Engineering Simulations from Cornell University ★★★★★(2)
  183. Front-End Web UI Frameworks and Tools: Bootstrap 4 from The Hong Kong University of Science and Technology
  184. Excel Skills for Business: Intermediate I from Macquarie University
  185. The Strategy of Content Marketing from University of California, Davis ★★★★☆(7)
  186. Gestión Empresarial Exitosa para Pymes from Pontificia Universidad Católica de Chile
  187. Cómo hacer una tesis from Universidad Nacional Autónoma de México ★★★★☆(1)
  188. Begin Programming: Build Your First Mobile Game from University of Reading ★★★★☆(8)
  189. Statistical Thinking for Data Science and Analytics from Columbia University ★★☆☆☆(19)
  190. Understanding Research Methods from University of London International Programmes ★★★★☆(15)
  191. Creative Problem Solving from University of Minnesota ★★★☆☆(18)
  192. Machine Learning with Python from IBM ★★★★★(2)
  193. Viral Marketing and How to Craft Contagious Content from University of Pennsylvania ★★★★☆(27)
  194. Fundamentals of Project Planning and Management from University of Virginia ★★★★☆(27)
  195. Data Science: Visualization from Harvard University ★★★★★(3)
  196. Google Cloud Platform Big Data and Machine Learning Fundamentals from Google Cloud ★★★☆☆(3)
  197. Tools for Data Science from IBM ★☆☆☆☆(3)
  198. Introduction to Computational Thinking and Data Science from Massachusetts Institute of Technology ★★★★☆(31)
  199. Operating Systems and You: Becoming a Power User from Google ★★☆☆☆(2)
  200. Introduction to Classical Music from Yale University ★★★★★(26)
  201. Buddhism Through Its Scriptures from Harvard University ★★★★☆(6)
  202. Introduction to Data Analysis Using Excel from Rice University ★★★☆☆(2)
  203. Introduction to Engineering Mechanics from Georgia Institute of Technology ★★★★★(168)
  204. De-Mystifying Mindfulness from Leiden University ★★★★★(87)
  205. Logical and Critical Thinking from University Of Auckland ★★★★★(13)
  206. Functional Programming Principles in Scala from École Polytechnique Fédérale de Lausanne ★★★★★(66)
  207. An Introduction to Interactive Programming in Python (Part 1) from Rice University ★★★★★(3292)
  208. Introduction to Search Engine Optimization from University of California, Davis ★★★★☆(5)
  209. Cybersecurity Fundamentals from Rochester Institute of Technology ★★★★★(23)
  210. Ser más creativos from Universidad Nacional Autónoma de México ★★★★☆(2)
  211. Getting and Cleaning Data from Johns Hopkins University ★★★☆☆(57)
  212. Introduction to Kubernetes from Linux Foundation
  213. Forensic Psychology: Witness Investigation from The Open University ★★★★★(18)
  214. Introduction to Marketing from The University of British Columbia ★★★★★(5)
  215. Data Structures from University of California, San Diego ★★★★☆(13)
  216. Databases and SQL for Data Science with Python from IBM ★★☆☆☆(1)
  217. Understanding the Brain: The Neurobiology of Everyday Life from The University of Chicago ★★★★★(28)
  218. Digital Skills: Digital Marketing from Accenture ★★★★☆(4)
  219. Data Visualization and Communication with Tableau from Duke University ★★★★☆(9)
  220. Tricky American English Pronunciation from University of California, Irvine ★★★★☆(14)
  221. Creative Writing: The Craft of Plot from Wesleyan University ★★★★☆(17)
  222. Advanced Writing from University of California, Irvine ★★★★☆(6)
  223. Greek and Roman Mythology from University of Pennsylvania ★★★★★(20)
  224. Data Analysis with Python from IBM ★★★★☆(1)
  225. Java for Android from Vanderbilt University ★☆☆☆☆(1)
  226. Getting Started with Essay Writing from University of California, Irvine ★★★★☆(13)
  227. Dog Emotion and Cognition from Duke University ★★★★☆(19)
  228. Introduction to Public Speaking from University of Washington ★★★★★(14)
  229. Introduction to User Experience Design from Georgia Institute of Technology ★★★☆☆(3)
  230. Introducción a Data Science: Programación Estadística con R from Universidad Nacional Autónoma de México ★★★★☆(2)
  231. Effective Problem-Solving and Decision-Making from University of California, Irvine ★★★★☆(12)
  232. Code Yourself! An Introduction to Programming from University of Edinburgh ★★★★☆(12)
  233. Influencing People from University of Michigan ★★★★☆(7)
  234. A Crash Course in Data Science from Johns Hopkins University ★★★★☆(22)
  235. How to Write a Resume (Project-Centered Course) from State University of New York ★★★★☆(11)
  236. Nutrición y obesidad: control de sobrepeso from Universidad Nacional Autónoma de México ★★★★★(1)
  237. JavaScript Introduction from World Wide Web Consortium (W3C)
  238. How to Learn Online
  239. Introduction to Logic from Stanford University ★★★☆☆(20)
  240. Computing in Python I: Fundamentals and Procedural Programming from Georgia Institute of Technology ★★★★★(174)
  241. How To Create a Website in a Weekend! (Project-Centered Course) from State University of New York ★★★★☆(6)
  242. Divide and Conquer, Sorting and Searching, and Randomized Algorithms from Stanford University ★★★★★(67)
  243. Management and Leadership: Growing as a Manager from The Open University ★★★★★(6)
  244. Introducción a la programación en Python I: Aprendiendo a programar con Python from Pontificia Universidad Católica de Chile ★★★★★(2)
  245. System Administration and IT Infrastructure Services from Google ★★★★☆(3)
  246. Managing Big Data with MySQL from Duke University ★★★★☆(6)
  247. Responsive Website Basics: Code with HTML, CSS, and JavaScript from University of London International Programmes ★★★★☆(26)
  248. Starting a Business 1: Vision and Opportunity from University of Leeds ★★★★★(75)
  249. Astronomy: Exploring Time and Space from University of Arizona ★★★★★(20)
  250. High-Impact Business Writing from University of California, Irvine ★★★☆☆(8)

If these courses don’t interest you, either browse our extensive catalog of 30,000 online courses or have a look at our thematic collections:

To see all our compilations, visit Class Central’s Collections.

Suparn Patra Profile Image

Suparn Patra

Suparn developed an interest in MOOCs through a project he worked on during his MSc in Artificial Intelligence. He joined Class Central as a Full Stack Engineer.

Comments 8

  1. Avatar

    Bani

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

    Reply
  2. Avatar

    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.

    Reply
  3. Avatar

    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 .

    Reply
  4. Avatar

    Muvaffak GÖZAYDIN

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

    Reply
    • Suparn Patra

      Suparn Patra

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

      Reply
  5. Avatar

    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

    Lesa

    Reply
  6. Avatar

    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.

    Reply
  7. Avatar

    Sally Mac

    Wow-this is great! T/you-Sally

    Reply

Leave a reply

Your email address will not be published. All comments go through moderation, so your comment won't display immediately.

This site uses Akismet to reduce spam. Learn how your comment data is processed.