DaisyDisk has been the default answer to "what is using my disk" for over a decade, and it earns that reputation. It is fast, the radial map is genuinely readable, and the one time price is fair. If you want a visualizer and nothing else, it is a sensible purchase.
The question worth asking is whether you want a visualizer, or a tool that also removes the things visualizers find. Those are different products, and the difference decides the price you pay over time.
The four questions that actually matter
- Does it show sizes, or does it also clean? Some tools find a 41GB folder and leave you to remove it manually in Finder. On a hidden path like
DerivedDataor a Docker disk image, that is a real gap. - Does it know application specific caches? A generic tree view shows a folder called
containers. A tool built with developers in mind can tell you that 41GB of it is the Docker disk image and that clearing it will delete your volumes. - Is it the only tool you need? Disk analysis does not tell you why the machine is slow. If swap is climbing, the biggest folder on the drive is irrelevant.
- What is the pricing model? One time, subscription, or free with a paid upgrade. Over five years, the difference between $9.99 once and $40 a year is $190.
The realistic alternatives
GrandPerspective (free, open source)
The original treemap on macOS, released under the GPL. It shows an honest proportional map and does nothing you did not ask for. The interface shows its age, navigation requires menu clicks rather than fluid zooming, and it has no cleanup features at all.
Best for: people who want free, auditable, read only analysis and do not mind an older interface.
OmniDiskSweeper (free)
A column browser sorted by size. No visualization, no cleanup, very fast. It is a good complement to a visualizer rather than a replacement, because reading numbers is sometimes faster than reading blocks.
Best for: text oriented people who want a sorted list and intend to delete manually.
CleanMyMac (subscription)
A full suite: cleanup, malware scanning, app uninstaller, performance modules. Polished and broad. The trade off is a yearly fee and a large surface area of automated behaviour, which some people are happy with and others are not.
Best for: non technical users who want one app to handle everything and are comfortable with a subscription.
macoptimize ($20 one time, 2 Macs)
Built for the same question from a developer angle. It combines a treemap analyzer, a live CPU, memory, swap and disk monitor, and a cleanup engine that knows the specific paths developers care about: Xcode DerivedData, iOS DeviceSupport, simulator runtimes, Docker.raw, node_modules, Gradle caches, npm and yarn stores.
It runs as a local dashboard on localhost:7777 with no account and no telemetry, shows the exact path and size of everything it found, and logs each cleanup to a History tab.
Side by side
| Tool | Visual map | Cleans up | Dev caches | Price |
|---|---|---|---|---|
| DaisyDisk | Yes | Manual | No | $9.99 one time |
| GrandPerspective | Yes | No | No | Free |
| OmniDiskSweeper | No | No | No | Free |
| CleanMyMac | Partial | Yes | No | $35 to $80 per year |
| macoptimize | Yes | Yes | Yes | $20 one time |
If your only need is "show me a map of my disk once", GrandPerspective is free and DaisyDisk is a nice upgrade. If you build software and lose 100GB a year to build output, container images and dependency folders, choose a tool that knows those paths by name. See what macoptimize includes for $20.
How to decide in one minute
- Free and read only, no cleanup: GrandPerspective or OmniDiskSweeper.
- Best looking map, manual cleanup, one time price: DaisyDisk.
- One app for everything, subscription: CleanMyMac.
- Treemap plus live monitoring plus developer cache cleanup, one time: macoptimize.
The realistic options, side by side
| Tool | Price | Strength | Gap |
|---|---|---|---|
| GrandPerspective | Free, open source | Fast treemap of any folder | Reads only, no cleanup, no monitoring |
| OmniDiskSweeper | Free | Sorted list of every large item | Dated interface, no categories, deletes by hand |
| DaisyDisk | One time, around $10 | Beautiful, fast visualizer | Visualizer only, no live metrics, no cache knowledge |
| CleanMyMac | Subscription from $35 to $80 per year | Polished, broad, includes malware scan | Recurring cost, and no developer cache awareness |
| macoptimize | $20 one time, 2 Macs | Monitoring plus named dev cache cleanup | No malware scanning, not a full system suite |
What to check before paying for any of them
- Does it name the path before deleting? A tool that shows a folder and its size lets you verify. A tool that shows a category name and a number asks for trust.
- Does it understand your workload? If you build software, a cleaner that does not mention DerivedData, node_modules or Docker is not going to find most of your reclaimable space.
- Is it one time or recurring? Over three years a $40 per year subscription costs $120. A one time purchase stays where it is.
- Does it need Full Disk Access? Some tools request it for complete scanning. That is a legitimate trade, but it should be a conscious one.
- Does it keep a log? A record of what was removed is what lets you connect a freed number to a folder that stopped working.
Deciding in one minute
If you only want to see where space went and you are comfortable in Terminal, a free visualizer is enough and this is not a purchase decision at all. If you build software on your Mac, the visualizer will show you the space and then stop, because deleting Library files, package manager stores and container images by hand is exactly the part where people make mistakes.
The useful split is between seeing and doing. Seeing is a solved problem and mostly free. Doing it safely, with named paths, sizes and a log, is where a tool earns twenty dollars once.
FAQ
Is a subscription ever worth it for a disk tool?
If you use the other parts of the suite, possibly. CleanMyMac includes malware scanning and app management, which a disk tool does not. If all you want is to see and clear disk space, a recurring fee for that single job is hard to justify against a one time purchase.
Do these tools need Full Disk Access?
Some ask for it to scan locations macOS otherwise hides, such as Mail and message data. macoptimize does not request it and runs with the permissions your user account already has, which means it only ever sees folders you could open yourself.
Can I use two of them together?
Yes, and a common pairing is a free visualizer for exploration plus a cleanup tool for the parts that regenerate. Nothing either tool does conflicts with the other, as long as you do not run two cleanups at the same moment on the same folders.
Is the free option good enough?
For finding large files and understanding a folder layout, yes. GrandPerspective and OmniDiskSweeper both do that well. What free tools do not do is identify which folders are safe to remove and then remove them, which is the step that carries the risk.