TreeSize Freefor Windows

TreeSize Free is a folder size analyzer from the German developer JAM Software. After scanning a drive or folder, it lists subfolders by size in a tree that looks like Windows File Explorer and draws a colored bar behind each row, so the largest folders stand out immediately. Expanding the tree leads down to individual files, and since version 4.8 a treemap—a chart that sizes rectangles by the space they use—is shown as the default disk chart alongside the list.

It suits home users trying to work out why their C: drive is full, and anyone who prefers comparing folder sizes in a familiar Explorer layout rather than a purely graphical map. A portable edition is available for running from a USB stick. However, the license covers private, non-commercial use only, and the program does not run on Windows Server, so business and server administration work calls for the paid Personal or Professional editions or a different tool.

Explorer-style tree

Folder sizes appear in a tree hierarchy with background bars that show relative size. Switching to the column view adds size, allocated space, file count, last access date and owner in one table. Results can be sorted by size, age or file type.

Treemap chart

A treemap chart represents the scan as nested rectangles proportional to size. Since version 4.8 it is the default disk chart, so the list and the map can be read side by side.

Fast MFT scanning

On local NTFS drives TreeSize Free reads the Master File Table (MFT) directly for faster scans; other drives are scanned with two parallel threads. Running it elevated includes folders a standard account cannot access.

Network and mobile scans

Besides local disks, it can scan network shares, cloud-synced drives and smartphones connected over MTP or WebDAV. USB sticks, SD cards and external HDDs or SSDs are detected automatically.

Filters and NTFS compression

Results can be filtered by wildcards, regular expressions or whole names. It shows files compressed with LZX or XPress along with NTFS compression rates, and it can apply NTFS compression to an entire folder branch.

PDF reports

Scan results can be printed or saved as a PDF report. Excel, HTML and CSV exports, duplicate file search and scheduled scans are reserved for the paid editions.

Features

The free edition includes the tree list, treemap, filters and PDF reports, which covers the core job of finding where space went. Duplicate detection, a top-largest-files filter and broader export formats belong to the paid editions, which limits deeper cleanup work.

Ease of Use

The Explorer-like tree needs no learning curve, and the program can be launched from the right-click menu of a folder or drive. The interface is available in English, German, French, Japanese and other languages.

Stability & Safety

There are no ads or bundled offers, and JAM Software states that scan data never leaves the PC. Since version 4.8 the program collects anonymous usage data, which can be turned off in the options. Version 4.8.1 (November 2025) fixed a possible DLL hijacking issue when installing into the user profile.

• SpaceSniffer — A portable, treemap-first disk analyzer distributed as freeware without a commercial-use restriction.
• WizTree — Also reads the MFT for very fast scans and combines a tree list with a treemap; free for personal use.
• WinDirStat — An open-source analyzer that shows a tree list, treemap and per-extension statistics together and is free for any use.

Can TreeSize Free be used at work?

No. TreeSize Free is licensed for private, non-commercial use only; business use requires TreeSize Personal or Professional.

Does TreeSize Free work on Windows 11?

Yes. Since version 4.8 it can be opened from the Windows 11 File Explorer context menu. Versions from 4.6 onward are 64-bit only, and support for Windows 8 and 8.1 ended with 4.8.

What is the difference between TreeSize Free and TreeSize Professional?

The free edition focuses on folder size analysis, a treemap and PDF reports. Professional adds duplicate search, scheduled scans, Excel, HTML and CSV exports, server scanning and up to 32 scan threads.

Is there a portable version of TreeSize Free?

Yes. JAM Software offers a portable download of TreeSize Free that runs from a USB drive.

Can TreeSize Free scan network drives?

Yes. It scans network shares and cloud drives, but running it on Windows Server or managing servers is reserved for the paid editions.

TreeSize Free is a solid pick for home Windows users who want to check folder sizes in a familiar Explorer-style tree. Fast MFT scanning and network support are generous for a free tool, but the non-commercial license and the cleanup features held back for paid editions lead to our editor rating of 4 out of 5.

Editor rating 4/5