DaisyDisk vs OmniDiskSweeper vs GrandPerspective

Part of: Do Mac cleaners work? An honest answer from people who build one (Choosing a tool)

Pick the picture you read best. DaisyDisk draws a circular map, GrandPerspective draws a treemap of rectangles, and OmniDiskSweeper lists files from largest to smallest. All three answer the same question: what is using my disk? If you are unsure, start with the free one, GrandPerspective.

DiskJoy is our product, and we also make a disk scanner, so we are not neutral. We took every fact below from each tool’s own page and left out what we could not confirm.

Side by side

DaisyDisk

Its site says it scans in seconds, supports internal and external drives and cloud storage, previews files, and can scan as an administrator to include hidden files. It also says it has safety protections for system files. The circular map suits people who like to click into a folder and see its parts.

OmniDiskSweeper

Its page describes it as a way to “quickly find large, unwanted files and sweep them into the trash”. If you only want a sorted list of the biggest things, a list is direct. The page we read did not state a price or the current macOS support, so check both before you download.

GrandPerspective

Its page says each file is a rectangle with an area proportional to its size, and files in the same folder sit together. It is open source and needs macOS 14 or higher. A treemap shows many items at once, which helps you spot one huge file or a folder full of small ones. Its feature list also includes deleting files and folders from the view.

Which one for which person

• You want to try without paying: GrandPerspective.
• You like a clean, clickable map and a one-time price: DaisyDisk.
• You want a plain sorted list: OmniDiskSweeper, once you have confirmed it runs on your macOS.
• You want a category view with a reclaimable estimate: DiskJoy’s scan, pre-alpha.

Before you delete anything

An analyzer shows big, not useless. A large block may be a Photos library, a virtual machine or a project you still need. Open the item, check what it is, and move it to the Trash rather than deleting it permanently. Space only comes back after you empty the Trash; see the Trash guide. If you are weighing disk analyzers against all-in-one cleaners, do Mac cleaners work covers that question.

How to read each picture

A circular map puts folders in rings. The centre is the folder you are in, and slices outside it are its contents. Click a slice to go deeper. It is good for exploring.

A treemap fills one rectangle with smaller ones. Bigger rectangles are bigger files. Files in one folder sit together. It is good for spotting a single outlier.

A sorted list has no picture at all. You read names and sizes from the top. It is good when you already suspect a few big files.

None of them is more accurate. They draw the same numbers in different ways. For a wider list that adds Disk Inventory X, see disk space analyzers compared, and for a pick if DaisyDisk’s price or macOS support is the sticking point, see DaisyDisk alternatives.

A fair test

Scan the same folder with each tool you are considering. Then check the top results against du -sh ~/* | sort -h in Terminal, which is read-only. If a tool shows something you cannot find in Finder, it may be counting a hidden folder or a different volume. Ask why before you act on it.

What the pages do not say

OmniDiskSweeper’s page gives no price, no license and no current macOS support; its table of versions stops at 10.13. We have not run it for this article, so we cannot say whether it works on your Mac. If that matters, read the current page or try one of the other two first. We would rather leave a gap than guess.

Safe, Risky, Never

Try a scan

If you want a fourth view, DiskJoy’s scan groups what it finds by category and reports a cautious estimate. It reads only, and cleanup is not built yet.

Sources and disclosure

DiskJoy is our product. Accessed 2026-10-05: https://daisydiskapp.com/ ; https://www.omnigroup.com/omnidisksweeper ; https://grandperspectiv.sourceforge.net/. Prices and requirements change, so check each page.