explaingit

imputnet/cobalt

40,379SvelteAudience · vibe coderComplexity · 2/5MaintainedLicenseSetup · easy

TLDR

Clean, ad-free media downloader for videos and audio from social platforms. Paste a link, get the file, no trackers, paywalls, or sign-ups.

Mindmap

mindmap
  root((cobalt))
    What it does
      Download videos
      Download audio
      No ads or trackers
    How it works
      Paste URL
      API processes
      Get file back
    Supported platforms
      Instagram
      Reddit
      SoundCloud
    Use cases
      Save social clips
      Extract audio
      Self-host instance
    Tech stack
      Svelte frontend
      JavaScript API
    Key features
      No sign-in needed
      Public content only
      Self-hostable

Things people build with this

USE CASE 1

Download a video from Instagram or Reddit without visiting sketchy third-party downloader sites.

USE CASE 2

Extract audio from a SoundCloud track or video clip for offline listening.

USE CASE 3

Run your own private media downloader instance on your server without relying on hosted services.

Tech stack

SvelteJavaScriptNode.js

Getting it running

Difficulty · easy Time to first run · 5min
Use freely for any purpose, but you must share modifications under the same license and provide source code to users.

In plain English

Cobalt is a media downloader that lets you save videos, audio, and other content from social media platforms directly to your device. The problem it addresses is that most online media downloaders are cluttered with advertisements, trackers, pop-ups, paywalls, and dark patterns that make a simple download feel like an obstacle course. Cobalt aims to be the clean, no-nonsense alternative: paste a link, get the file, done. The way it works is by accepting a URL from a supported platform, processing the request through its API, and returning the media file directly to you. The project describes itself as working like a fancy proxy, it never caches any content, it just fetches and passes through what is publicly available. The platforms mentioned in the project topics include Instagram, Reddit, and SoundCloud, among others. There is no sign-in required, no account, and no tracking. The README notes that cobalt can only download free and publicly accessible content, and that the same content could be retrieved manually through a browser's developer tools. You would use cobalt if you want to save a video or audio clip from a social media platform without dealing with intrusive third-party downloader sites. You can use the hosted version at cobalt.tools, or you can run your own instance using the provided self-hosting documentation. The monorepo includes the API, the frontend web interface, and related packages. The tech stack is Svelte for the frontend web interface, with a JavaScript API backend, all licensed under AGPL-3.0.

Copy-paste prompts

Prompt 1
How do I use cobalt to download a video from Instagram? Walk me through the steps.
Prompt 2
Show me how to self-host cobalt on my own server using the documentation.
Prompt 3
What social media platforms does cobalt support for downloading content?
Prompt 4
Can I use cobalt to extract audio from a YouTube or TikTok video? Explain what's possible.
Prompt 5
Help me set up a cobalt instance and integrate it into my workflow for batch downloading videos.
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.