Skip to content
A cross platform Electron based disk usage analyzer
JavaScript CSS HTML
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.


package version stability

Observatory was made out of a desire for a higher quality and modern disk usage analysis tool for Windows, Linux, and macOS utilizing the sunburst graph type. Other alternatives out there are either slow, old, ugly, platform specific, or some combination of all of these.

Observatory checks all the boxes that no one else does.

  • Pretty ✔
  • Modern ✔
  • Cross platform ✔
  • Fast ✔ (sort of)
  • Memory efficient ✔ (sort of)

The last two are both things that are kind of work-in-progress. On a modern SSD the loading times are reasonable to wait for and memory usage isn't really an issue, although both could definitely be improved. You're more than welcome to help improve them if you want.

Observatory is open source and available free of charge. I put a lot of love and work into it, and if you'd like to show appreciation I'd be incredibly thankful!


To build Observatory, you'll first need to install the latest versions of Node.js and Yarn. Once installed, clone this repository to your computer and run yarn inside of it to install the rest of Observatory's dependencies.

To run in development:

yarn start

Build for release:

yarn forge


  • DaisyDisk: 13.20s - 219.7MB
  • VirtualFileSystem v1: 48.841s
  • VirtualFileSystem v2: 77.896s

VFS v1 is still monstrously faster for some reason, even though v2 is basically exactly the same thing, and if anything is lighter weight. I don't get it.

DaisyDisk will probably always be faster since it can optimize specifically for macOS and runs directly on hardware instead of inside of V8, but I have no interesting in rewriting Observatory natively any time soon since that would really complicate my goal of being cross platform. That being said, it is still a goal to improve performance and figure out why there was such a major regression in v2.


Full scan in less than 30 seconds on a MacBook Pro

  • Currently takes about 60 seconds on my MacBook Pro and 25.5 seconds on my Windows desktop
You can’t perform that action at this time.