CS50

@cs50 · 2.5M subscribers · 750 videos · newest 750 of 2,457

A course from this channel is on Best free Python courses on YouTube, ranked by total hours

Total watch time

24d 17h 15m

at speed · exactly 24 days, 17 hours, 15 minutes at 1×

24d 17h 15m
1.25×19d 18h 36m
1.5×16d 11h 30m
1.75×14d 3h
12d 8h 37m 30s
Average video47m 28s
Longest5h 25m 16s
Shortest4s
Counted back to2020
Open on YouTube All uploads as a playlist JSON

Playlists (200+)

Every public playlist on the channel — open one for its full breakdown

Lengths are calculated on demand so this page stays fast.

#PlaylistVideosLength
1 CS50x en Español 13 length →
2 CS50x em Português 13 length →
3 CS50 Office Hours Reels 8 length →
4 CS50 Tech Talks 1 length →
5 Teasers - CS50's Introduction to 2D Game Development 8 length →
6 CS50 Seminars - Fall 2025 1 length →
7 CS50x Lectures 13 length →
8 CS50x 2026 Sections 9 length →
9 CS50's Computer Science for Business 10 length →
10 CS50's Introduction to 2D Game Development 9 length →
11 CS50 Fair 2024 at Yale 14 length →
12 CS50 Fair 2024 at Harvard 15 length →
13 CS50's 48-Hour Film Projects 4 length →
14 CS50 Seminars - Fall 2024 1 length →
15 CS50 Sections - Fall 2024 9 length →
16 CS50x 2025 Lectures 13 length →
17 CS50's Introduction to Programming with R 8 length →
18 CS50P Shorts 35 length →
19 CS50 Fair 2023 at Yale 10 length →
20 CS50 Fair 2023 at Harvard 17 length →
21 CS50x 2024 Lectures 12 length →
22 CS50's Introduction to Cybersecurity 6 length →
23 CS50 Educator Workshop 2023 9 length →
24 CS50's Introduction to Artificial Intelligence with Python 2023 8 length →
25 CS50's Introduction to Databases with SQL 8 length →
26 Visitas Thinks Big 2023 - Harvard University 4 length →
27 CS50 Fair Harvard 2022 10 length →
28 CS50x 2023 Lectures 12 length →
29 CS50 Fair Yale 2022 12 length →
30 CS50 Intros 6 length →
31 CS50 Educator Workshop 2022 7 length →
32 Hello, CS50x 24 length →
33 CS50P Shorts 2022 3 length →
34 CS50's Introduction to Programming with Python (CS50P) 2022 11 length →
35 CS50 Reels 45 length →
36 Visitas Thinks Big 2022 - Harvard University 4 length →
37 About CS50 3 length →
38 CS50 Lectures 2021 (HDR) 13 length →
39 CS50 Lectures 2021 (SDR) 12 length →
40 CS50 Seminars 2021 7 length →
41 CS50 Educator Workshop 2021 5 length →
42 Teasers - CS50's Introduction to Game Development 11 length →
43 Passing TCP/IP Packet - CS50 2020 4 length →
44 CS50 Lectures 2020 13 length →
45 Walkthroughs - CS50 Labs 2020 9 length →
46 CS50 Walkthroughs 2020 1 length →
47 CS50 Lectures 2020 (pre-release) 13 length →
48 CS50 Office Hours 2020 Clips 34 length →
49 Office Hours with David and Brian 13 length →
50 CS50's Web Programming with Python and JavaScript (CS50W) 2020 10 length →
51 CS50's Introduction to Artificial Intelligence with Python 2020 8 length →
52 CS50 Fair 2019 38 length →
53 CS50 Lecture Clips 2019 11 length →
54 CS50 2019 - Walkthroughs - Speller 6 length →
55 CS50 2019 - Games Track 27 length →
56 CS50 2019 - Android Track 7 length →
57 CS50 2019 - Web Track 10 length →
58 filter (more comfortable) 5 length →
59 filter (less comfortable) 5 length →
60 CS50 2019 - iOS Track 7 length →
61 CS50 Lectures 2019 9 length →
62 CS50 Walkthroughs 2019 29 length →
63 Visitas Thinks Big 2019 - Harvard University 4 length →
64 CS50 Podcast 12 length →
65 CS50 for Lawyers 2019 11 length →
66 CS50 Beyond 2019 12 length →
67 CS50 Plays Twitch 2 length →
68 CS50 Seminars 2018 6 length →
69 CS50 on Twitch 63 length →
70 CS50 Lecture Clips 2018 10 length →
71 CS50 Lectures 2018 11 length →
72 CS50 en Español 2018 23 length →
73 Visitas Thinks Big 2018 - Harvard University 4 length →
74 CS50 Tech Talks 2018 3 length →
75 CS50 en Español 2017 13 length →
76 CS50's Introduction to Game Development 2018 13 length →
77 CS50's Mobile App Development with React Native 2018 14 length →
78 CS50's Web Programming with Python and JavaScript 13 length →
79 Mispellings 4 length →
80 CS50 Seminars 2017 11 length →
81 Sentimental 8 length →
82 CS50 Shorts 50 length →
83 CS50 Tech Talks 2017 4 length →
84 CS50 Supersection 2017 2 length →
85 CS50 Lectures 2017 13 length →
86 CS50's Computer Science for Business Professionals 2017 6 length →
87 CS50's Understanding Technology 2017 6 length →
88 CS50 Presents: Project 5050 14 length →
89 CS50 Explained 2016 in Virtual Reality 46 length →
90 CS50 AP Workshop 2017 8 length →
91 Visitas Thinks Big 2017 5 length →
92 A Celebration of CS at Harvard in Honor of Harry Lewis 10 length →
93 Visitas Puzzles 2017 Solutions 5 length →
94 CS50 Live in VR, Season 3 2 length →
95 CS50x Puzzle Day 2017 Solutions 8 length →
96 CS50 Live Clips, Season 3 12 length →
97 CS50 Live, Season 3 4 length →
98 WeCode 2017 Keynotes 3 length →
99 CS50 Music Videos 4 length →
100 CS50 Explained 2016 46 length →
101 CS50 Sections 2015 50 length →
102 HSA Dev Bootcamp 2016 19 length →
103 Mashup 3 length →
104 C$50 Finance 8 length →
105 Sentiments 3 length →
106 CS50 Puppetry 9 length →
107 CS50 Outros 2016 13 length →
108 Mashup 2 length →
109 C$50 Finance 9 length →
110 CS50 Seminars 2016 11 length →
111 CS50 VR around the World 33 length →
112 CS50 VR Lectures 2016 14 length →
113 CS50 Puzzle Day 2016 3 length →
114 CS50 Lectures 2016 14 length →
115 CS50 Walkthroughs 46 length →
116 CS50x Coding Contest 2016 Postmortems 10 length →
117 Computer Science for Business Leaders - July 2016 8 length →
118 Visitas Thinks Big 2016 5 length →
119 CS50 Seminars 2016 1 length →
120 Computer Science for Business Leaders, March 2016 8 length →
121 CS50 AP Cambridge Workshop 2016 5 length →
122 WECode 2016 9 length →
123 CS50x Puzzle Day 2016 50 length →
124 CS50 Fairs 2015 2 length →
125 CS50 Performances 2015 10 length →
126 CS50 Hackathon 2015 4 length →
127 AI Series 3 length →
128 Week 10 2015 Section 4 length →
129 2015 MDC 2 length →
130 Week 9 2015 Walkthroughs 9 length →
131 Week 9 Section 2015 4 length →
132 Week 8 2015 Walkthroughs 7 length →
133 Performances 2015 9 length →
134 CS50 Seminars 2015 17 length →
135 Week 8 Section 2015 6 length →
136 Week 7 2015 Walkthroughs 19 length →
137 Week 7 2015 Section 5 length →
138 Week 6 2015 Section 3 length →
139 CS50 Yale Sections 2015 7 length →
140 CS50 2015 Seinfeld50 13 length →
141 Week 5 2015 Section 7 length →
142 Week 4 2015 Section 9 length →
143 Week 3 2015 Section 6 length →
144 Week 5 2015 Walkthroughs 3 length →
145 Week 4 2015 Walkthroughs 13 length →
146 Week 3 2015 Walkthroughs 3 length →
147 Week 9 2015 Shorts 1 length →
148 Week 8 2015 Shorts 3 length →
149 Week 7 2015 Shorts 4 length →
150 Week 6 2015 Shorts 4 length →
151 Week 5 2015 Shorts 3 length →
152 Week 4 2015 Shorts 7 length →
153 Week 3 2015 Shorts 7 length →
154 Week 2 2015 Shorts 9 length →
155 Week 0 2015 Shorts 5 length →
156 Week 2 2015 Walkthroughs 17 length →
157 Week 1 2015 Shorts 10 length →
158 Week 1 2015 Walkthroughs 13 length →
159 Week 0 2015 Walkthroughs 15 length →
160 CS50 Lectures 2015 24 length →
161 CS50 Lectures 2007 30 length →
162 CS50 Lectures 2008 22 length →
163 CS50 Lectures 2009 21 length →
164 CS50 Lectures 2010 22 length →
165 CS50 Lectures 2011 22 length →
166 CS50 Explained 2014 9 length →
167 CS50 Hackathon at Miami Dade College 3 length →
168 Visitas Thinks Big 2015 7 length →
169 CS50's Deep Thoughts by Daven Farnham 11 length →
170 Week 9 2014 9 length →
171 Week 8 2014 13 length →
172 CS50 Seminars 2014 17 length →
173 Week 7 2014 16 length →
174 Week 5 2014 5 length →
175 Week 4 2014 19 length →
176 Week 3 2014 3 length →
177 Week 2 2014 14 length →
178 CS50 Lectures 2014 22 length →
179 Week 1 2014 11 length →
180 Performances 2014 9 length →
181 Week 0 2014 15 length →
182 Teasers 5 length →
183 2014 Talks 1 length →
184 Harvard Tour 5 length →
185 Segments 21 length →
186 CS50 Live 20 length →
187 CS50 Fair 2013 in Slow Motion 89 length →
188 CS50 Reviews 2013 2 length →
189 CS50 Performances 1 length →
190 CS50 Shorts 2013 2 length →
191 Week 9 2013 39 length →
192 CS50 Seminars 2013 9 length →
193 Week 7 2013 6 length →
194 CS50 Outtakes 2013 2 length →
195 CS50 Walkthroughs (Lectures) 102 length →
196 Week 5 2013 12 length →
197 Week 4 2013 9 length →
198 Week 3 2013 12 length →
199 CS50 Sections 2013 12 length →
200 Week 2 2013 9 length →

Showing the first 200 playlists.

Uploads by year

7 years (newest uploads only)
YearVideosWatch timeAverage
2026844d 22h 14m1h 24m 27s
2025744d 1h 56m1h 19m 25s
20241463d 7h 35m32m 42s
20231603d 18h 22m33m 53s
20221503d 11h 7m33m 15s
2021573d 3h 54m1h 19m 54s
2020792d 7m36m 33s

Longest uploads

Top 5 · 5h 25m and down
  1. Second Day of CS50 Educator Workshop 2023 · 5:25:16 · 2023-07-01
  2. CS50 2D - Lecture 0 - Pong (live, unedited) · 4:05:05 · 2025-06-09
  3. CS50 Business - Lecture 6 - Weaving the Web (live, unedited) · 3:32:55 · 2025-06-24
  4. CS50 Business - Lecture 3 - Practicing Programming (live, unedited) · 3:31:41 · 2025-06-19
  5. CS50 2D - Lecture 5 - Legend of Zelda (live, unedited) · 3:24:25 · 2025-06-24

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Watch time: 24d 17h 15m · 750 videos

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Data from the YouTube Data API as of 2026-09-22 (cached). Uploads are counted newest first; private, deleted and live videos are excluded from totals.