Which fits your needs?
OmniDiskSweeper: Mac users who prefer a free size-sorted browser to a chart.
WhatSize: Mac users who favor column browsing and integrated duplicate/cleanup tools.
Features, pricing, and workflow
Scroll across to compare
| Feature | OmniDiskSweeper | WhatSize |
|---|---|---|
| Best fit | Mac users who prefer a free size-sorted browser to a chart. | Mac users who favor column browsing and integrated duplicate/cleanup tools. |
| Visualization | Largest-first column browser | Size-sorted columns and measurement views |
| Platforms and requirements | macOS | macOS 11+ (current vendor requirements) |
| Pricing and editions | Free download from The Omni Group. | Vendor lists $14.99 and a 30-day trial; upgrades may be priced separately. |
| Open source | No | No |
| Native macOS UI | Yes | Yes |
| Cleanup workflow | Open or Trash selected files from the size-sorted browser. | Review the chosen cleaning or duplicate action before applying it. |
| Reports and portability | The official overview does not document report export. Keep important paths separately before rescanning in NullDisk. | Preserve any saved measurements or reports supported by your version. The cited overview does not establish an import format shared with NullDisk. |
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
WhatSize: what stands out
A good fit for Mac users who favor column browsing and integrated duplicate/cleanup tools.
WhatSize: strengths
- Size-sorted columns and detailed filtering
- Duplicate-file tools and cleanup categories
- Updates measurements as the filesystem changes
Considerations
- Paid license after the trial
- Cleanup categories still require your judgment
- Check upgrade terms separately from the initial purchase
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 OmniDiskSweeper?
A good fit for Mac users who prefer a free size-sorted browser to a chart. Free download from The Omni Group.
When should I choose WhatSize?
A good fit for Mac users who favor column browsing and integrated duplicate/cleanup tools. Vendor lists $14.99 and a 30-day trial; upgrades may be priced separately.
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.