[opensourcedex]

cobalt is a free, open source collaboration & communication project written in Svelte and released under AGPL-3.0. It has 43,316 GitHub stars, 3,798 forks and 269 open issues, and was last pushed 5 months ago. On this registry it ranks #3 of 41 tracked projects in Collaboration & Communication, with 5 head-to-head comparisons available. It gained 84 stars over the last 3 tracked days.

What is cobalt?

What it is

cobalt is a media downloader built around a single promise: paste a link, get the file, move on. It is a monorepo containing the source for an API, a web frontend, and related packages, written primarily in Svelte and TypeScript. The project lives in the modern web and JavaScript ecosystem, and its public surface is hosted at cobalt.tools, while the full codebase is published under the AGPL-3.0 license.

The concrete problem it solves is friction and monetization around saving media. According to its README, cobalt is a downloader that "doesn't piss you off" — it ships without ads, trackers, paywalls, or other interruptions between a person and the content they want. It targets sources named in its topic list, including Instagram, Twitter, TikTok, Reddit, SoundCloud, and music more broadly, letting users retrieve free and publicly accessible media without wading through browser extensions, sketchy mirrors, or JavaScript-dev-tools spelunking.

Key capabilities

  • Downloads media from social and audio sources listed in the topics: Instagram, Twitter, TikTok, Reddit, and SoundCloud.
  • Serves as a monorepo with separate api, web, and packages trees, so the backend and frontend can be developed and deployed together.
  • Operates as a stateless proxy: the README states cobalt never caches any content and "works like a fancy proxy."
  • Restricts itself to free and publicly accessible content, and the README argues the same content is reachable through any modern browser's dev tools.
  • Publishes API documentation in the docs tree, including an API reference for integrators.
  • Documents instance environment variables, so operators can configure a self-hosted deployment.
  • Includes guidance on protecting a cobalt instance, aimed at self-hosters running public endpoints.

Who uses it and how

  • Individuals paste a media link into the hosted cobalt.tools frontend and receive the file directly.
  • Self-hosters follow the "how to run a cobalt instance" documentation to stand up their own API and web frontend.
  • Operators running a public instance consult the "how to protect a cobalt instance" guide and the API environment-variable reference.
  • Developers integrate against the documented cobalt API rather than scraping platforms themselves.
  • Contributors work inside the monorepo's api and web trees after reading the contribution guidelines.

Getting started

The README points to the docs tree for running an instance and

project readme (upstream, from github) — read inline

best way to save what you love
cobalt.tools

💬 community discord server
🐦 twitter 🦋 bluesky


cobalt is a media downloader that doesn't piss you off. it's friendly, efficient, and doesn't have ads, trackers, paywalls or other nonsense.

paste the link, get the file, move on. that simple, just how it should be.

cobalt monorepo

this monorepo includes source code for api, frontend, and related packages:

it also includes documentation in the docs tree:

ethics

cobalt is a tool that makes downloading public content easier. it takes zero liability. the end user is responsible for what they download, how they use and distribute that content. cobalt never caches any content, it works like a fancy proxy.

cobalt is in no way a piracy tool and cannot be used as such. it can only download free & publicly accessible content. same content can be downloaded via dev tools of any modern web browser.

contributing

if you're considering contributing to cobalt, first of all, thank you! check the contribution guidelines here before getting started, they'll help you do your best right away.

thank you

cobalt is sponsored by royalehosting.net. a part of our infrastructure is hosted on their network. we really appreciate their kindness and support!

licenses

for relevant licensing information, see the api and web READMEs. unless specified otherwise, the remainder of this repository is licensed under AGPL-3.0.

Frequently asked questions

Is cobalt free to use?

cobalt is open source under the AGPL-3.0 licence. There is no licence fee and no seat count — you can self-host it or, where the project offers one, pay a vendor for a managed version instead.

What does cobalt do?

best way to save what you love

What is cobalt written in?

cobalt is primarily written in Svelte. Its source is publicly available at https://github.com/imputnet/cobalt, and it has 43,316 GitHub stars.