cobalt
Cobalt is an ad-free, privacy-respecting media downloader that lets you paste a link from social and video platforms and get the original file back. It's a monorepo with a Svelte web frontend and a self-hostable API that streams content like a proxy without caching.
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[](https://opensources.dev/resource/cobalt)AGPL-3.0-onlyNetwork copyleft (AGPL) — even offering it over a network (SaaS) can trigger the source-sharing requirement.View license →
Production readiness
4/5- Actively maintainedCommits in the last 6 months
- No known vulnerabilitiesNo OSV advisories
- Clear, usable licenseAGPL-3.0-only (network copyleft)
- Proven adoptionWidely used
- Has documentationDocumentation indexed
npm install cobaltOur analysis
A web-based media downloader application with a Svelte frontend and a self-hostable Node API. Users paste a URL from supported platforms and cobalt fetches and streams the underlying file without ads, trackers, or caching.
When to use cobalt
Use it when you want a clean, no-nonsense tool to download publicly accessible media from many platforms, either via the hosted instance or by self-hosting your own API for privacy and control.
When not to
Reach for a CLI tool like yt-dlp if you need scriptable, headless batch downloading, format selection scripting, or integration into automated pipelines. Cobalt is a UX-focused app, not a programmable library.
Strengths
- Clean, ad/tracker-free user experience focused on simplicity
- Acts as a stateless proxy that never caches content, reducing storage and liability concerns
- Self-hostable API with documented environment variables and instance hardening guides
- Very popular and actively maintained with a large community
Trade-offs
- Dependent on platform support which can break as sites change their APIs
- Legal/ToS gray area depending on jurisdiction and platform terms
- Self-hosting requires infrastructure and may face rate-limiting or IP blocks from target sites
- AGPL-3.0 licensing imposes copyleft obligations on derivative deployments
Maturity
Mature and widely adopted (40k+ stars) with active development, a structured monorepo, public API docs, hosting sponsorship, and an active community across Discord and social platforms.
Cobalt is an ad-free, privacy-respecting media downloader that lets you paste a link from social and video platforms and get the original file back. It's a monorepo with a Svelte web frontend and a self-hostable API that streams content like a proxy without caching.