NullDisk our pick
A native macOS disk-space analyzer with an interactive radial map. Native SwiftUI, allocated-size honesty with hard-link dedup, staged Trash-based removal, local disk scans.
GrandPerspective
Fully free, open source, and genuinely powerful. The default answer to 'what's free?'.
Disk Inventory X
Free classic with treemaps and type breakdowns, revived for modern Macs.
SquirrelDisk
Free open-source sunburst on every desktop OS. Java UI, honest price: zero.
OmniDiskSweeper
Free largest-first browser. Spartan, fast, trustworthy vendor.
Space Radar
Free MIT-licensed visualizer with sunburst, treemap, and flamegraph — for tinkerers.
DiskPoint
Free privacy-focused cleanup with offline visualization on three platforms.
How we compare
Free means free: we favored tools with no paywall on core analysis, then judged visualization, honesty of measurement, and whether deletions are safe. Freemium teasers rank below fully-free tools.
Frequently asked questions
What's the best completely free disk analyzer for Mac?
GrandPerspective — open source, fast, and its treemap finds the biggest hog in seconds. Pair it with Disk Inventory X for type breakdowns.
Are free cleaners safe?
Analyzers are safe; automated cleaners deserve scrutiny. Prefer tools that stage deletions (or just use the Trash) over ones that nuke with one click.
Why pay for NullDisk when free tools exist?
All NullDisk features are free indefinitely, including cleanup and workplace use. An optional one-time purchase supports development and removes reminders.