How do I download a YouTube video as MP3?

Select 'MP3 Audio', paste the YouTube URL, click Fetch, then Download. The audio file saves to your device.

Can I download a full YouTube playlist?

Yes. Paste the playlist URL (youtube.com/playlist?list=…). Enter a free YouTube Data API v3 key to load the track list, select which videos to download, then click Download Selected.

Does this work without installing anything?

Yes — it runs entirely in your browser. The backend is a self-hosted cobalt instance deployed on your own server via deploy.sh. No third-party services are used.

📥 YouTube to MP3 / MP4

Download videos as MP4 or audio as MP3 — single videos and full playlists with batch download.

About YouTube Downloader

Want to save a YouTube video for offline viewing, or extract just the audio as an MP3 to listen on the go? Paste the video URL, choose whether you want the full MP4 video or audio-only MP3, and download it directly. Playlist support lets you queue up an entire playlist for batch download — handy for saving a full course, album, or video series at once.

This connects to a backend server that handles the download and sends the file back to you, so it works without any browser extensions or software installs. Great for saving educational content, lectures, music, and tutorials for offline access. Please only download content you have the right to use — respect copyright and the platform's terms of service.

🔧 Under Maintenance — YouTube downloads need a one-time cookie setup (operator: click to expand)

YouTube blocks downloads from datacenter/VPS IPs with a "Sign in to confirm you're not a bot" check. The PO-token provider (office-tools-pot) is running and healthy, but on a flagged server IP that alone is not enough — YouTube requires authenticated cookies. There is no fully autonomous way to mint these on the server: the initial Google login must be done by a human (Google's login flow blocks datacenter logins with CAPTCHA/2FA). Cookies then last weeks, not forever, and must be re-exported when downloads start failing again.

① Create cookies (one time, on your local computer)

Use a throwaway Google account — never your real one. Server-side scraping can get the account flagged or banned.
Install the "Get cookies.txt LOCALLY" browser extension.
Open a private / incognito window and log into youtube.com with the burner account.
With a normal video open, click the extension → Export → save cookies.txt (Netscape format).
Close the incognito window WITHOUT logging out. Logging out invalidates the session server-side — this is the #1 reason server cookies "work for an hour then die."

② Install on the server & enable

# after copying cookies.txt to the VPS (scp):
install -o www-data -g www-data -m 600 cookies.txt /opt/office-tools/yt-server/cookies.txt
grep -q '^YTDLP_COOKIES=' /opt/office-tools/yt-server/.env \
  || echo 'YTDLP_COOKIES=/opt/office-tools/yt-server/cookies.txt' >> /opt/office-tools/yt-server/.env
systemctl restart office-tools-cobalt
curl -s http://127.0.0.1:9000/health   # "cookies" should change from "none" to "file:ok"/"file:unchecked"

③ Renew (when the bot-check returns weeks later)

Health shows "cookies":"file:expired" or downloads fail again. Re-export with the exact same incognito method above, then replace the file:

install -o www-data -g www-data -m 600 cookies.txt /opt/office-tools/yt-server/cookies.txt
systemctl restart office-tools-cobalt

Note: yt-dlp rewrites rotated cookies back into this file on each use, so it must stay writable by www-data. Cookie upkeep is inherent to running a YouTube downloader from a server IP — it is not a bug in the tool.

Format

⚡ cobalt — self-hosted cobalt server. MP4 up to 1080p + MP3.

YouTube URL

Video quality

⚙️ Advanced — server URL

⚡ cobalt server URL

Default: /yt-api/ — your self-hosted cobalt instance (deployed by deploy.sh step 1, proxied via nginx). Change only if running cobalt on a custom port or path.

download MP4 YouTube to MP3 save video video downloader playlist download