Harvard CS50x 2025: study plan and how long it takes
The CS50 playlist is 13 videos and 26.4 hours long. Here's how long it takes at different paces, a week-by-week schedule built from the real videos, and a planner that turns it into your own daily plan.
13 videos · 26.4 hours · CS50
CS50x is Harvard's introduction to computer science, taught by David J. Malan and released free on YouTube. The 2025 lecture playlist goes from Scratch to C, Python, SQL and web development with Flask, and it is one of the most popular first courses for people learning to program.
Most lectures run over two hours, so a plan matters. The lectures are only half of CS50: each week also has a problem set, and those usually take longer than the lecture itself. Budget time for both.
Who it's for: Complete beginners and self-taught developers who want a solid grounding in how computers and programs work. No prior experience is needed.
How long does it take?
The full playlist is 26.4 hours across 13 videos. Here's roughly how many days that is at different daily watch times and speeds, counting video time only:
| Daily time | At 1x | At 1.5x | At 2x |
|---|---|---|---|
| 30 min a day | 53 days | 36 days | 27 days |
| 1 h a day | 27 days | 18 days | 14 days |
| 2 h a day | 14 days | 9 days | 7 days |
Make your own schedule
The playlist link is already filled in. Press Plan, set how much time you have each day and your speed, and you'll get a day-by-day schedule with a finish date and a calendar file. It reads the live playlist, so new videos are included.
Week-by-week schedule
A sample plan at 1 hour a day and normal speed, using whole videos so none is split across days. That's 2 weeks in total. For a different pace, start date or speed, use the planner above.
Week 1Videos 1–7 · 13h 22m
Day 1 · 2m
- 1CS50x 2025 - Introduction2m
Day 2 · 1h 59m
- 2CS50x 2025 - Lecture 0 - Scratch1h 59m
Day 3 · 2h 35m
- 3CS50x 2025 - Lecture 1 - C2h 35m
Day 4 · 2h 10m
- 4CS50x 2025 - Lecture 2 - Arrays2h 10m
Day 5 · 2h 7m
- 5CS50x 2025 - Lecture 3 - Algorithms2h 7m
Day 6 · 2h 27m
- 6CS50x 2025 - Lecture 4 - Memory2h 27m
Day 7 · 2h 4m
- 7CS50x 2025 - Lecture 5 - Data Structures2h 4m
Week 2Videos 8–13 · 13h
Day 8 · 2h 11m
- 8CS50x 2025 - Lecture 6 - Python2h 11m
Day 9 · 56m
- 9CS50x 2025 - Artificial Intelligence56m
Day 10 · 2h 38m
- 10CS50x 2025 - Lecture 7 - SQL2h 38m
Day 11 · 3h 14m
- 11CS50x 2025 - Lecture 8 - HTML, CSS, JavaScript3h 14m
Day 12 · 3h 4m
- 12CS50x 2025 - Lecture 9 - Flask3h 4m
Day 13 · 57m
- 13CS50x 2025 - Lecture 10 - The End57m
Study plan, phase by phase
Video numbers are positions in the playlist. To schedule just one phase, enter its numbers in the planner's From and To fields.
- 01
Weeks 0–2: Scratch, C and arrays
Videos 1–4 · 6h 45m
The introduction, Scratch, C and arrays. Lecture 1 on C is the longest of the early lectures and the first big jump, so give it two sittings and start Problem Set 1 before moving on.
- 02
Weeks 3–5: Algorithms, memory and data structures
Videos 5–7 · 6h 37m
Searching and sorting, pointers and memory, then linked lists, trees and hash tables. This is the hardest stretch of CS50 and where most people stall. Slow down here rather than rushing to Python.
- 03
Weeks 6–7: Python, AI and SQL
Videos 8–10 · 5h 45m
Python feels fast after C. The playlist also includes a one-hour Artificial Intelligence lecture, then SQL and databases.
- 04
Weeks 8–10: Web, Flask and the final project
Videos 11–13 · 7h 15m
HTML, CSS and JavaScript (the longest lecture, over three hours), Flask, and the closing lecture. Leave a couple of weeks after this for your final project.
Tips for finishing
- Plan one lecture per week if you're doing the problem sets. A daily-time schedule of 30 to 45 minutes covers the lecture with room for practice on the other days.
- Watch the long lectures at 1.25x and pause for the code demos. The planner shows exactly how much time that saves.
- Do the problem sets on cs50.harvard.edu as you go. Watching all 13 lectures first and coding later is the most common way people fail to finish.