TreeSize

ApplicationJAM Software

Also called treesize free, treesize professional, jam treesize

JAM SoftwareSystem

A paid disk-space map from JAM Software. A free edition exists. The process is TreeSize.exe. It is not WinDirStat.

What you need to know

TreeSize is JAM's disk map. WinDirStat is a different free treemap.

JAM Software TreeSize shows which folders use space. Free and paid editions exist. Get them from jam-software.com. It is not WinDirStat and it is not WizTree's MFT reader.

What is it?: A disk-space map from JAM
Same as WinDirStat?: No. Different product and license
Is there a free build?: Yes. TreeSize Free exists

Feex says

If you need a folder-size tree and your shop already bought JAM, that is TreeSize. If you wanted a free treemap, I would open WinDirStat or WizTree instead of paying on the first day.

What is TreeSize?

TreeSize is JAM's folder-size scanner. TreeSize.exe is the paid family. TreeSize Free is a separate download. WinDirStat is a different treemap project.

If you have never used it

If a drive is full and you want a licensed folder map, TreeSize is JAM Software's disk-space tool. The free edition exists. Paid TreeSize adds more views and reports. Download it from jam-software.com. It is not WinDirStat, not WizTree, and not Storage Sense.

What is it used for?

See which folders eat the drive

Scan a drive or a share. The tree of sizes is the product. WinDirStat draws a treemap instead of JAM's paid reports.

Export and schedule on paid SKUs

Professional adds reports and file-search extras. That is why shops pay. WizTree is not this license.

Free edition for a one-off look

TreeSize Free is enough for a home PC. It is still TreeSize, not windirstat.exe.

Who is it for?

Admins who want a licensed disk map
Home users who grabbed TreeSize Free
Anyone comparing this to WinDirStat or WizTree

Current status

TreeSize (1996) is a current disk space analyzer from JAM Software. The vendor still points Windows users at https://www.jam-software.com/treesize.

How old is it?

TreeSize dates to 1996. It is older than WinDirStat (2003) and much older than WizTree (2016). JAM still sells current Windows builds. A Windows 95 screenshot is history.

Versions

Major channels first. Exact build numbers are not all verified here.

TreeSize Free

TreeSize Personal

TreeSize Professional

System requirements

Values follow the publisher's public guidance. Workload still changes the real need.

Minimum

Minimum system requirements
Operating system	Windows 10 or Windows 11, per JAM Software's current TreeSize pages
RAM	Enough for Windows plus this app. Heavy projects want more.

Resource profile

CPU demand: Rises while walking the tree
Disk demand: Lots of metadata reads during a scan

Installed processes

These executables belong to this product when it is installed.

Installed processes
TreeSize.exe	Disk map window
TreeSizeFree.exe	Free edition image name on some installs

Startup components

TreeSize should not start with Windows unless you scheduled a paid scan.

File locations

Common TreeSize locations
Typical install	C:\Program Files\JAM Software\TreeSize\

File formats

Exports reports on paid SKUs. It reads the file system

Common problems

Free versus paid confusion

TreeSize Free is not Professional. The Start tile and the license dialog name the SKU. WinDirStat has no JAM key.

Slow scan on a huge network share

Permissions and latency cost time. WizTree's MFT shortcut does not apply the same way on a UNC path.

Getting unstuck

Download from jam-software.com, not a "TreeSize crack" host

JAM sells licenses. WinDirStat is the free treemap if you did not want to pay.

Run as administrator if Program Files folders show as small

Access denied hides size. That is NTFS permissions, not a broken WizTree MFT read.

Pick TreeSize Free if you only needed a one-off map

The free edition is enough for many home PCs. Professional is the paid product, not WinDirStat.

Alternatives

WinDirStat for a classic free treemap. WizTree for a fast NTFS MFT scan. Storage Sense does not draw this map.

Official help and downloads

Start with the vendor. Random exe sites are not a support channel.

Official contacts
Download	www.jam-software.com/treesize Official installer or vendor page
Help	knowledgebase.jam-software.com/ Vendor support
Official site	www.jam-software.com/treesize Start here, not a random exe host

Related hardware

The scan reads the file system. An HDD feels slower than NVMe. That is the drive, not a GPU score.

Technical details

Vendor version numbers change. This article does not pin a build.

Sources and verification

Reviewed by Feex editorial. Last verified August 2026 Status: Feex Reviewed. How we research.

TreeSize official site · Vendor product page
TreeSize help · Vendor support
TreeSize Free · Free edition product page
Foxhole process map · First-party samples on Windows PCs. Not a lab benchmark.

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