Which fits your needs?
SquirrelDisk: People wanting a free open-source GUI across desktop systems and remote storage.
WhatSize: Mac users who favor column browsing and integrated duplicate/cleanup tools.
Features, pricing, and workflow
Scroll across to compare
| Feature | SquirrelDisk | WhatSize |
|---|---|---|
| Best fit | People wanting a free open-source GUI across desktop systems and remote storage. | Mac users who favor column browsing and integrated duplicate/cleanup tools. |
| Visualization | Sunburst, treemap, file list, and duplicates | Size-sorted columns and measurement views |
| Platforms and requirements | macOS, Windows, Linux | macOS 11+ (current vendor requirements) |
| Pricing and editions | Free; AGPL-3.0 source published on GitHub. | Vendor lists $14.99 and a 30-day trial; upgrades may be priced separately. |
| Open source | Yes | No |
| Native macOS UI | Cross-platform interface | Yes |
| Cleanup workflow | Collector offers Trash, permanent removal, secure erase, or backup before deletion. | Review the chosen cleaning or duplicate action before applying it. |
| Reports and portability | The current overview does not establish an interoperable scan-report format. Preserve paths, duplicate decisions, and remote source settings separately. | Preserve any saved measurements or reports supported by your version. The cited overview does not establish an import format shared with NullDisk. |
SquirrelDisk: what stands out
A good fit for people wanting a free open-source GUI across desktop systems and remote storage.
SquirrelDisk: strengths
- Live maps and a staged removal collector
- Content-based duplicate search
- SSH and rclone-backed cloud storage
Considerations
- Uses a cross-platform Rust interface rather than SwiftUI
- Permanent deletion and secure erase require deliberate review
- Cloud/SSH actions depend on provider and remote-system support
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 SquirrelDisk?
A good fit for people wanting a free open-source GUI across desktop systems and remote storage. Free; AGPL-3.0 source published on GitHub.
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.