Our verdict: SpaceSniffer is a quick way to see what is eating your disk space: big folders and files show up as big blocks in a treemap. Filters by type, size, age and color tags help narrow things down. It is portable and free, but the animated layout takes getting used to and it does not delete duplicates for you.
About SpaceSniffer
SpaceSniffer is a free, portable disk analyzer from Uderzo Software. It scans a drive or folder and draws it as a treemap, where the size of each block matches the size of the folder or file. Clicking a block shows its contents in more detail, and double-clicking zooms it to fill the window. Version 2, released in 2025, is a 64-bit build that is still updated.
A filter field narrows the view, for example to *.jpg, to files larger than 1 MB, or to files older than two years, and filters can be combined or inverted. You can tag files in four colors while reviewing them and filter by tag. An export module writes text reports with a layout you can customize.
What it does well
- Treemap view. Folder and file sizes shown as nested blocks that update during the scan.
- Drill down and zoom. Click for more detail, double-click to zoom into a folder.
- Filters. Combine file type, size and age filters, or exclude matches.
- Color tags. Mark files in four colors and filter by tag.
- Text reports. Export results with a customizable report layout.
Who it is for
Good fit
Anyone who wants to find large forgotten folders quickly on a full drive.
Look elsewhere
Users who prefer a sorted list view, or who want automatic duplicate cleanup.
Pros and cons
Pros
- Free and portable
- Treemap makes big files obvious
- Powerful combined filters
- Still updated, with a 64-bit build
Cons
- Treemap view can feel busy at first
- No built-in duplicate finder
- Closed source
How to install SpaceSniffer
SpaceSniffer is portable: download the ZIP from the official page, extract it and run SpaceSniffer.exe, then pick a drive or folder to scan. The developer asks sites to link the download page rather than the archive, so the button here opens that page.
Questions about SpaceSniffer
Is SpaceSniffer free?
Yes. It is freeware; the developer accepts donations.
Does SpaceSniffer need to be installed?
No. It is a portable program: extract the ZIP and run it.
