Honest comparison
AudioFetcher vs cobalt
Both are ad-free web tools with no account. cobalt is open source, supports many sites and can be self-hosted. AudioFetcher focuses on YouTube audio and adds playlists, original Opus and M4A, FLAC, chapters, SponsorBlock and tag editing. cobalt's maintainers have reported that YouTube limits restrict downloads on the public cobalt.tools instance since mid-2025.
Written by the AudioFetcher team, so we have an interest. Facts about cobalt come from its own site, documentation or linked sources. Last checked September 17, 2026.
Side by side
| AudioFetcher | cobalt | |
|---|---|---|
| Platform | Web app in any modern browser; optional Firefox extension | Web app at cobalt.tools; open-source (AGPL) and self-hostable |
| Install | None | None for cobalt.tools; a server for self-hosting |
| Account | Not needed for free conversions | Not needed |
| Price | Free for single videos up to 60 minutes. Supporter Pass: $5 one-time for 30 days, no subscription. | Free |
| Ads and pop-ups | None | None |
| Output formats | MP3 (up to 320 kbps, VBR options), FLAC, original Opus, original M4A, MP4 (up to 720p free) | MP3, Opus, OGG, WAV or best available; bitrate 8 to 320 kbps; video downloads |
| Keeps original YouTube audio | Yes, Opus and M4A are delivered without re-encoding | A "best" audio option is available |
| Length limits | Free: 60 minutes of audio per video, one MP4 per day up to 20 minutes. Supporter: audio up to 12 hours, FLAC up to 2 hours, MP4 up to 60 minutes | No published length limit found |
| Playlists | Full playlists and queues of up to 100 links with a Supporter Pass; a free Library Pack of up to 10 items once a day | No playlist support; requested repeatedly on GitHub |
| Extras | ID3 tag editing and embedded cover art (MP3), chapter embedding and splitting, SponsorBlock sponsor removal, subtitles, LRCLIB lyrics file, ordered playlist ZIP | Automatic cover art and subtitle downloads since version 11.2 (June 2025); many sites besides YouTube |
| Checks before converting | One Cloudflare Turnstile check before a free conversion | Varies by instance |
| Where conversion runs | On AudioFetcher's servers; files are temporary and deleted automatically | On the cobalt instance you use; the project describes a zero-log policy |
YouTube on cobalt.tools
In June 2025 users opened GitHub issue #1356, "Can't download videos from YouTube on cobalt.tools". On August 15, 2025 a maintainer wrote that strict network limits on YouTube's side were still present and that the project could not get around them at its scale. The issue was still open when we checked. Self-hosted instances may behave differently, and the situation can change, so try a YouTube link yourself before relying on either tool.
Choose cobalt if
- You want open-source software you can audit or run on your own server.
- You download from many sites, not just YouTube.
- You only need single files and not playlists.
Choose AudioFetcher if
- You mainly convert YouTube audio and want the original Opus or M4A stream, or FLAC.
- You need whole playlists in order, chapters split into tracks, sponsor segments removed, or MP3 tags and cover art set before download.
- You do not want to run a server.
Other comparisons
Sources
- cobalt on GitHubProject README: open source, supported services, self-hosting.
- cobalt about pageNo ads, no tracking, zero-log policy.
- cobalt 11.2 changelog, June 30, 2025Automatic cover art and subtitle downloads.
- GitHub issue #1356YouTube download limits on cobalt.tools; maintainer update August 15, 2025.
- GitHub issue #193Playlist support request.
Other tools change often. If something here is out of date, email help@audiofetcher.com and we will correct it.