A GrandPerspective alternative, and when to keep GrandPerspective
GrandPerspective is a good free treemap and worth keeping for what it does. Here is what it covers, what it does not, and when to want something else.
GrandPerspective is one of the oldest treemap tools on the Mac and it is genuinely good at the thing it does. This page is not an argument that you should stop using it. It is an account of where it stops, so you can tell which side of that line your problem is on.
What it does well
- A real treemap. Every file becomes a rectangle sized by how much space it uses, which is still the fastest way to see where a drive went.
- Free, and open. There is no subscription and no upsell, and the App Store price exists to support the project rather than to unlock anything.
- Single purpose. It shows disk usage. It does not offer to speed up your Mac or clean a registry, which is more than can be said for much of this category.
- Long standing. It has been maintained for many years, which counts for something in a category full of abandoned tools.
Where it stops
These are not defects. They are the boundary of what a pure treemap can know.
| Question | A plain treemap |
|---|---|
| What is this 4 GB folder? | Shows the path, leaves the meaning to you |
| Does this app still exist? | No concept of applications, only files |
| Will this come back if I remove it? | No distinction between a cache and a document |
| Which of these are duplicates? | Not something a size map can answer |
| What is my Mac doing right now? | Out of scope |
The practical version of that table: a treemap tells you a folder is large, and you are then on your own to work out whether it matters. For a folder full of holiday photos that is fine. For a support folder belonging to an application you removed two years ago, it is the whole difficulty.
The macOS version, which decides it for some people
The current release requires macOS 14 or later. Older releases cover earlier systems, and the project keeps them available, but you are then running an older build. Free Mac runs on macOS 10.15 and later, so on an older Mac that is kept deliberately, this is the practical difference rather than any feature.
Who should use GrandPerspective
Take it, and stop reading, if you want one free tool that draws a map and nothing else, you are on macOS 14 or later, and you are comfortable deciding for yourself what each large folder is. That is a completely reasonable set of requirements and it is exactly what the tool is for.
When to want something else
The map is the beginning of the job rather than the end of it. If your large folders are ones you cannot identify, then the useful tool is one that also knows what it is looking at: which app a support folder belongs to, which folders are build output that will regenerate, and which files are duplicates of each other. Those are covered in uninstall leftovers and finding duplicates.
Free Mac scans without a licence and always will, so the honest way to decide is to draw both maps and see which one answers your question. If the other tool answers it, use the other tool.
For the two commercial options in this category, see the DaisyDisk comparison and the CleanMyMac comparison.
Common questions
Is GrandPerspective free?
Yes. It is a free download from SourceForge, and the same application is on the Mac App Store for $2.99, where the price supports the project rather than unlocking anything. Checked 5 September 2026.
What macOS does GrandPerspective need?
Version 3.8.0, released 24 August 2026, requires macOS 14 or later on Apple silicon or Intel. Older releases remain available for earlier systems. Checked 5 September 2026.
What can a treemap not tell you?
Whether a large folder matters. A treemap sizes files accurately but has no concept of which application a support folder belongs to, whether a folder is build output that will regenerate, or which files duplicate each other. Those need a tool that understands what it is looking at.