YouTube Video Downloader using Python

Install the yt-dlp library

I’m going to use uv as my package manager but you can use pip or any other package manager you prefer.

uv init --bare
uv add yt-dlp

Verify the installation

To verify that the yt-dlp library has been installed correctly, you can run the following command:

uv run yt-dlp --version

Install ffmpeg

The yt-dlp library requires ffmpeg to process video and audio files. You can download it from ffmpeg.org  and follow the installation instructions for your operating system.

For Windows, so I’m using winget to install ffmpeg.

winget install "FFmpeg (Essentials Build)"
ffmpeg -version

For Ubuntu, you can use apt to install ffmpeg.

sudo apt update
sudo apt install ffmpeg -y
ffmpeg -version

[Optional] Run the command to download a YouTube video

This step is optional, but you can try run the following command to download a YouTube video. For me I’m going to download a video in mp3 format.

uv run yt-dlp -f bestaudio/best -x --audio-format mp3 -o <path-to-save> <youtube-video-url>

Here is an sample output when I run the command:

PS C:\Users\karchunt\Desktop\tutorial> uv run yt-dlp -f bestaudio/best -x --audio-format mp3 -o ./output/test.mp3 https://www.youtube.com/watch?v=IViaa3o7BbU
[youtube] Extracting URL: https://www.youtube.com/watch?v=IViaa3o7BbU
[youtube] IViaa3o7BbU: Downloading webpage
[youtube] IViaa3o7BbU: Downloading tv simply player API JSON
[youtube] IViaa3o7BbU: Downloading tv client config
[youtube] IViaa3o7BbU: Downloading tv player API JSON
[info] IViaa3o7BbU: Downloading 1 format(s): 251
[download] Sleeping 5.00 seconds as required by the site...
[download] Destination: output\test.webm
[download] 100% of    4.11MiB in 00:00:00 at 23.39MiB/s
[ExtractAudio] Destination: output\test.mp3
Deleting original file output\test.webm (pass -k to keep)

Create and execute a Python script to download YouTube videos

Alright, now let’s create a Python script that uses the yt-dlp library to download subsequent YouTube videos.

import os
import yt_dlp
 
# Replace with your desired YouTube video URL
url = "youtube-video-url"
ydl_opts = {
  'format': 'bestaudio/best',
  'postprocessors': [{
    'key': 'FFmpegExtractAudio',
    'preferredcodec': 'mp3',
    'preferredquality': '320', # 0 for highest quality VBR
  }],
  'outtmpl': os.path.join("./", '%(title)s.%(ext)s'),
}
 
with yt_dlp.YoutubeDL(ydl_opts) as ydl:
  ydl.download([url])

import os
import subprocess as s
 
# Replace with your desired YouTube video URL
url = "youtube-video-url"
download_format = 'bestaudio/best'
s.call(['yt-dlp', '-f', download_format, '-x', '--audio-format', 'mp3', '-o', os.path.join('./', '%(title)s.%(ext)s'), url])

The reason I set preferredquality to 320 is because I want to download the audio in the highest quality possible. FYI, preferredquality set to 0 does not always product the highest quality audio because of how the FFmpeg encoder works.

• The parameter 0 maps to a variable bitrate (VBR) setting which tells the FFMpeg to use the highest VBR quality, which results in a bitrate ranging between 220-260kbps.

However, there are some nuances:

• VBR is often better quality: VBR typically produces better quality than CBR (Constant Bitrate) at similar file sizes because it allocates bits more efficiently based on audio complexity.
• 320kbps CBR vs VBR comparison: While 320kbps CBR guarantees consistent bitrate, VBR-0 (highest quality VBR) often produces perceptually equivalent or better quality at lower average bitrates.

# For guaranteed 320kbps constant bitrate
'preferredquality': '320'
 
# For highest quality VBR (often better quality, smaller files)
'preferredquality': '0'

So it depends on your use case. If you want guaranteed 320kbps, go with 320. If you want the best quality possible and don’t mind variable bitrate, go with 0.

Finally, run the Python script to download the YouTube video.

uv run yt.py