See what's eating your disk. Instantly.

Yes, completely. OpenDisk is MIT-licensed open source. There is no trial, no paid tier, no locked features, and no account. If you find it useful, a star on GitHub is appreciated.

OpenDisk reads directory metadata in bulk using the getattrlistbulk(2) and searchfs(2) kernel APIs instead of statting files one by one, and runs a worker pool tuned to how APFS serializes directory reads. On a 1 TB cold scan that means 17 seconds versus DaisyDisk's 37. Repeat scans are 20 to 28x faster still, because OpenDisk replays filesystem events instead of rescanning everything.

OpenDisk requires macOS 26 (Tahoe) or later, and runs natively on both Apple Silicon and Intel.

Without Full Disk Access, macOS hides parts of the filesystem and the totals come up short. OpenDisk prompts on first launch; grant it in System Settings → Privacy & Security → Full Disk Access. Nothing leaves your machine: there's no telemetry, and the code is open so you can verify that.

OpenDisk updates itself via Sparkle, the same open-source update framework trusted by hundreds of Mac apps. It checks the appcast on this site, verifies the EdDSA signature on every download, and installs with one click. You can also grab any release manually from GitHub.

Please do. Fork the repository, make your improvement, and open a pull request. For fundamental changes, open an issue to consult the maintainer first.