SoftNexi

Windows · System & Disk Utilities

SpaceSniffer for Windows

Free, portable disk-space visualizer that draws a zoomable, filterable treemap of a drive with no installation required.

Updated August 9, 2026 · Reviewed by SoftNexi Editorial Team, Software research and documentation

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Overview

SpaceSniffer is a lightweight, portable disk usage visualizer built around a treemap similar in concept to WinDirStat's, but with a filter box that lets you type patterns (like *.mp4 or a folder name) to instantly highlight or isolate matching items within the scan.

Because it's a single portable executable with no installer, it's convenient to keep on a USB drive for troubleshooting other people's machines, or to run on a system where you don't want to install anything.

The visualization updates live as it scans, so you can start clicking into large folders before the entire scan finishes, which is handy on a very large or slow drive.

It hasn't seen frequent updates in recent years; it still generally works on current Windows versions, but if you want an actively developed, faster-scanning alternative, WizTree is worth comparing.

Key features

  • Zoomable treemap visualization of disk usage
  • Live-updating results as the scan progresses
  • Filter box to isolate files by name pattern or extension
  • Fully portable — a single executable, no installation
  • Right-click delete, open, or explore actions on treemap tiles

System requirements

Operating system
Windows 11 and Windows 10 (older Windows releases also supported)
Installation
Portable — runs as a single executable with no installer
Permissions
Administrator rights recommended for scanning system folders

How to install SpaceSniffer

  1. 1. Download the executable

    Get the ZIP or standalone .exe from the developer's official download page.

  2. 2. Run directly

    No installation step is needed — just run the executable, optionally from a USB drive.

  3. 3. Select a folder to scan

    Point SpaceSniffer at a drive or specific folder to begin the live treemap scan.

How to use it

  1. 1. Watch the live scan

    The treemap fills in as SpaceSniffer scans, so you can start exploring large folders before the whole drive finishes.

  2. 2. Filter by pattern

    Type a pattern like *.iso or *.log in the filter box to highlight or isolate matching files across the entire scanned tree.

  3. 3. Zoom into a folder

    Double-click a rectangle to zoom into that folder and see its contents in more detail.

  4. 4. Clean up from the treemap

    Right-click a tile to delete, open, or reveal that file or folder in Explorer.

Safety and privacy

  • Download from the developer's own uderzo.it site rather than third-party portals.
  • Being a single portable executable, there's no installer to review, but only run copies obtained from the official source.
Bundled software
The official download is a standalone executable with no bundled offers.
Privacy
Runs entirely locally with no account or network requirement.

Known risks

  • Development has been infrequent, so newer NTFS or Windows quirks may not be as polished as in actively maintained tools.

What's new

  • Current release

    SpaceSniffer has seen infrequent updates in recent years. It generally still runs on current Windows versions; check the developer's site for the latest confirmed compatibility.

Pros and cons

Pros

  • Fully portable with no installation required
  • Filter box adds a useful search layer on top of the visual treemap
  • Live-updating scan is convenient on large drives
  • Free

Cons

  • Infrequent updates in recent years
  • Interface looks dated
  • Slower raw scan speed than MFT-based tools like WizTree

Verdict

SpaceSniffer's portability and live filtering make it a handy pocket tool for a quick space check on any machine, especially from a USB drive. For a faster scan on very large drives or more active development, WizTree is the better long-term choice.

Frequently asked questions

Do I need to install SpaceSniffer?

No, it's a single portable executable — download and run it directly, including from a USB drive.

Is SpaceSniffer free?

Yes, it's free donationware from Uderzo Software.

Is SpaceSniffer still maintained?

Updates have been infrequent in recent years. It generally still works on current Windows versions, but check the developer's site for the latest status before relying on it exclusively.