Which fits your needs?
GrandPerspective: People who want a free, inspectable treemap and reusable scan records.
OmniDiskSweeper: Mac users who prefer a free size-sorted browser to a chart.
Features, pricing, and workflow
Scroll across to compare
| Feature | GrandPerspective | OmniDiskSweeper |
|---|---|---|
| Best fit | People who want a free, inspectable treemap and reusable scan records. | Mac users who prefer a free size-sorted browser to a chart. |
| Visualization | Treemap with configurable colors and filters | Largest-first column browser |
| Platforms and requirements | macOS 14+ (current release) | macOS |
| Pricing and editions | Free from SourceForge; the same app is $2.99 in the US App Store. | Free download from The Omni Group. |
| Open source | Yes | No |
| Native macOS UI | Yes | Yes |
| Cleanup workflow | Delete files or folders from the view; review selection and deletion preferences. | Open or Trash selected files from the size-sorted browser. |
| Reports and portability | Save the scan for reopening in GrandPerspective, or export text and images. NullDisk does not import GrandPerspective scan files; retain exports and rescan the same location. | The official overview does not document report export. Keep important paths separately before rescanning in NullDisk. |
GrandPerspective: what stands out
A good fit for people who want a free, inspectable treemap and reusable scan records.
GrandPerspective: strengths
- Configurable colors, masks, searches, and scan exclusions
- Quick Look, Finder integration, and file/folder deletion
- Save/reload scans and export text or images
Considerations
- Treemap rather than radial navigation
- Older macOS versions require an older release
- App Store updates can follow SourceForge releases later
OmniDiskSweeper: what stands out
A good fit for Mac users who prefer a free size-sorted browser to a chart.
OmniDiskSweeper: strengths
- Largest-first file and folder browsing
- Open items or move them to Trash
- Official downloads include versions for older Macs
Considerations
- Column browsing rather than a graphical disk map
- Check the download requirements for your macOS version
- The cited overview does not document saved reports or duplicate matching
For a useful comparison on your own drive, match the scan root, access permissions, and size mode. Chart style changes how you explore the results; it does not by itself establish measurement accuracy.
Common questions
When should I choose GrandPerspective?
A good fit for people who want a free, inspectable treemap and reusable scan records. Free from SourceForge; the same app is $2.99 in the US App Store.
When should I choose OmniDiskSweeper?
A good fit for Mac users who prefer a free size-sorted browser to a chart. Free download from The Omni Group.
Will both apps show the same size?
Not necessarily. Match the scan root, permissions, exclusions, and logical/allocated-size mode. Hard links, APFS clones, snapshots, sparse files, and cloud placeholders can change totals. A reported size is not a guaranteed amount recovered after deletion.