What WhatSize is
WhatSize by id-design, inc. is a list disk analyzer for macOS. Pricing is paid (Paid one-time license (around $15 at time of writing)). The official site is linked below — always download disk tools from the vendor, never from aggregators.
| WhatSize | |
|---|---|
| Vendor | id-design, inc. |
| Platform | macOS |
| Pricing | Paid — Paid one-time license (around $15 at time of writing) |
| Visualization | List |
| Open source | No |
Updated September 2026 · Prices change — please verify with the vendor.
Strengths & Weaknesses
＋ Strengths
- Deep measuring with column, outline, and chart views
- Finds large, duplicate, and orphaned files beyond simple sizes
- Appeals to power users who live in column browsers
－ Weaknesses
- Dense, technical UI with a real learning curve
- Paid license with no free tier for casual use
- Visualization is secondary to tables and lists
Who WhatSize is for
Fans of list visualization on macOS. If instead you want a native Mac sunburst with a staged, Trash-based cleanup and zero telemetry, that's NullDisk's whole pitch.
The NullDisk alternative
- A radial sunburst map instead of lists or treemaps — see usage at a glance and drill in with a click.
- Honest one-time purchase instead of subscriptions or gated tiers.
- Fully offline with a published zero-data policy — nothing ever leaves your Mac.
WhatSize vs NullDisk → · See alternatives → · Switching guide →
Frequently asked questions
Is WhatSize worth it?
WhatSize is worth a look if you like list views and paid pricing on macOS. A fast measuring sorter with column views and cleanup tools. For a native Mac map with a staged cleanup workflow, compare it against NullDisk before deciding.
Is WhatSize safe?
WhatSize is as safe as its workflow: it deletes from ranked lists. Whatever you choose, prefer tools that stage deletions or use the Trash — which is exactly how NullDisk's collector works.
Does WhatSize work on Apple Silicon?
Yes — WhatSize runs on modern Macs, including Apple Silicon. If nativeness matters to you, NullDisk is built SwiftUI-first for macOS 14 and up.
Bottom line
WhatSize: deep measuring with column, outline, and chart views — but dense, technical UI with a real learning curve. Weigh that trade honestly against NullDisk's native map, staged collector, and zero-data promise.
Also consider
- OmniDiskSweeper — A largest-first column browser for quick, no-frills cleanup. (OmniDiskSweeper vs WhatSize →)
- Disk Xray — All-in-one analyzer, duplicate finder, uninstaller, and shredder. (Disk Xray vs WhatSize →)
- SimplyDiskSweeper — A minimal sorted-list cleaner for quick disk sweeps. (SimplyDiskSweeper vs WhatSize →)