Free Disk Tools — The 10 Best for Cleanup, Partitions, USB Boot and Drive Health
Search for a free disk cleanup or partition tool and you get “best of” lists where many entries are trials, “free editions” that lock the important operations, or cleaners that come with ads and bundled software. We read the main comparison pages on the web — SoftPicker, StoredBits, How-To Geek, MindGems, SoftwareTestingHelp, iTechGuides, Gitnux and AlternativeTo — and in October 2026 we checked every tool ourselves: licence, platforms and what the free use really allows.
For an engineer the disk is a work tool: simulation result folders, meshes, point clouds and project backups fill hundreds of gigabytes, and a drive that starts to fail can take years of work with it. This article covers five jobs: finding what takes up the space, cleaning temporary and duplicate files, changing partitions, preparing a bootable USB stick for a reinstall, and checking drive health before it breaks. For each tool we list advantages and disadvantages, and above all who may use it free.
Comparison table: the top 10
| Tool | Platforms | Licence in plain words | Best for |
|---|---|---|---|
| CrystalDiskInfo | Windows | Open source, free for commercial use too | Health checks of HDD, SSD and NVMe |
| WizTree | Windows | Free for personal use only; commercial use is paid | The fastest scan of an NTFS drive |
| WinDirStat | Windows | Open source, free for commercial use too | A disk-usage map on a work PC |
| Rufus | Windows | Open source, free for commercial use too | A USB stick to install Windows or Linux |
| Ventoy | Windows, Linux | Open source, free for commercial use too | Many ISO files on one drive |
| BleachBit | Windows, Linux | Open source, no ads and no Pro edition | Cleaning temporary files and caches |
| Czkawka / Krokiet | Windows, macOS, Linux | Open source, free for commercial use too | Duplicate files and similar images |
| GParted | Linux (Live USB for any PC) | Open source, free for commercial use too | Growing, shrinking and moving partitions |
| GSmartControl + smartmontools | Windows, macOS, Linux | Open source, free for commercial use too | S.M.A.R.T. tests and server monitoring |
| CrystalDiskMark | Windows | Open source, free for commercial use too | Measuring drive speed |
The top 10
1. CrystalDiskInfo
Reads the S.M.A.R.T. data of every drive in the PC and shows health status, temperature, power-on hours and total data written, including NVMe drives, some external USB drives and Intel RAID. Run it before trusting a disk that holds years of project files, and before buying a second-hand computer.
Advantages: open source under MIT, free for any use including commercial. Leave it in the background to get an alert, even by email, when a value degrades.
Disadvantages: Windows only. The download page lists installer variants marked Ads, so pick the Standard Edition (ZIP or regular installer). It warns about a problem but does not fix it and does not replace a backup.
2. WizTree
Reads the file table of an NTFS drive directly, so it scans a whole drive in seconds. It shows the largest folders and files in a list and a treemap, finds duplicate files and exports the list to CSV. Simulation engineers use it to find result and mesh files that take up tens of gigabytes.
Advantages: the fastest tool in the category according to most comparison pages, with a clear list of the largest files on the drive.
Disadvantages: not free for everyone: it is free for personal use only. Commercial use requires buying a Supporter Code, and organisations can buy an Enterprise licence. Windows only.
3. WinDirStat
Scans a drive or folder and shows the space as a coloured treemap in which every large file stands out at once, next to a sorted folder tree and statistics by file type. It also finds duplicates and exports to CSV.
Advantages: open source (GPL-3.0), free for any use including commercial, with no registration and no licence key — the safe choice for an office PC. A portable version is available.
Disadvantages: Windows only, and scanning a large hard disk is much slower than with WizTree.
4. Rufus
Turns a USB stick into a boot drive from an ISO image: a clean install of Windows or a Linux distribution, running diagnostic tools, or flashing BIOS and firmware from DOS.
Advantages: open source (GPL-3.0 or later), free for any use. A small program that runs without installation and supports UEFI and legacy BIOS. The official website shows ads, but the program itself does not.
Disadvantages: Windows only. Each run writes one system and erases the whole drive.
5. Ventoy
Installs a boot loader on the USB stick once; from then on you just copy ISO, WIM, IMG or VHD files to it and pick from a menu what to boot. One drive holds Windows installers, several Linux distributions and GParted Live together, and the rest of the space stays free for normal files.
Advantages: open source (GPL-3.0 or later), free for any use. No reformatting each time, with support for UEFI, legacy BIOS and Secure Boot, files over 4 GB and Linux persistence.
Disadvantages: a few rare images do not boot through it, and then you need Rufus. The project is developed mainly by a single developer.
6. BleachBit
Deletes temporary files, browser and program caches, system logs and leftovers from applications, and lists the files to be removed before cleaning. It suits a PC full after years of installs, and Linux servers via its command line.
Advantages: open source (GPL-3.0), free for any use, with no ads, no registration and no nagging Pro edition. You can write your own cleaning rules and shred files so they cannot be recovered.
Disadvantages: review every checkbox: some options delete passwords saved in the browser. There is no macOS version.
7. Czkawka / Krokiet
Finds duplicate files by name, size or content, plus similar images and videos, empty folders and files, big files, broken links and files with the wrong extension. It suits a project server where the same drawings and PDFs were saved many times.
Advantages: open source (MIT and GPL-3.0), free for any use, with no ads and no data collection. Fast, caches results for repeat scans, and runs on Windows, macOS and Linux.
Disadvantages: two interfaces can confuse: Krokiet is the recommended one, and the older GTK interface will not get new releases. Similar-image results need careful review before deleting.
8. GParted
A graphical partition editor: it creates and deletes partitions, grows and shrinks them without losing data, moves, copies and formats them in NTFS, FAT32, exFAT, ext4 and more. On a Windows PC you use GParted Live from a USB stick, for example to enlarge drive C after moving to a bigger SSD.
Advantages: open source (GPL-2.0 or later), free for any use — the only partition tool that appears in every list with no locked “free edition” and no upgrade offers.
Disadvantages: you must boot from the stick and leave Windows. There is no automatic system cloning like in commercial tools, and a wrong operation can erase data — back up before any change.
9. GSmartControl + smartmontools
smartmontools is the engine: smartctl reads S.M.A.R.T. data and runs self-tests, and smartd runs in the background and sends an alert when a drive degrades. GSmartControl is its graphical front end, which highlights abnormal values and starts a short or extended test with one click.
Advantages: open source (GPL), free for any use, on Windows, macOS and Linux. smartd suits a file server, NAS or compute workstation that runs for days, and GSmartControl is also included in GParted Live.
Disadvantages: some USB adapters and RAID controllers do not pass the data through. smartmontools has no graphical interface. Download GSmartControl only from the official site or GitHub: the developer warns that a similar .com domain is a phishing site.
GSmartControl
Alexander Shaduri
A graphical front end to smartctl for checking disk health, running S.M.A.R.T. self-tests and spotting early signs of failure.
Get it from the vendor
smartmontools
smartmontools developers
The smartctl and smartd command-line tools for reading S.M.A.R.T. data, running self-tests and continuously monitoring server disks.
Get it from the vendor10. CrystalDiskMark
Measures read and write speed in MB/s, both sequentially for large files and in random access to small blocks — the figure that decides how fast a heavy model or a project with thousands of files opens. Use it to check whether a new SSD delivers what was promised, or to test an office network drive.
Advantages: open source (MIT), free for any use. Results copy as text into a report.
Disadvantages: Windows only, with the same caveat about the Ads variants on the download page. A synthetic measurement only, which does not check drive health.
More free disk tools worth knowing
Disk-space analysis: TreeSize Free opens straight from the Explorer menu, but it is for private, non-commercial use only and does not run on Windows Server. On Linux, QDirStat shows a WinDirStat-style treemap with statistics by file type, and KDE’s Filelight shows a simple ring map, on Windows too.
TreeSize Free
JAM Software
Shows which folders take up disk space, right from the Explorer menu — for private, non-commercial use only.
Get it from the vendor
QDirStat
Stefan Hundhammer
A WinDirStat-style disk-usage map for Linux: a folder tree and a coloured treemap that show what takes up space.
Get it from the vendor
Filelight
KDE
An interactive ring map of disk usage from KDE, for Linux and Windows, to spot heavy folders quickly.
Get it from the vendorFlashing SD cards: balenaEtcher writes an ISO or IMG file to a USB stick or SD card in three steps, verifies the write and hides system drives — handy for a Raspberry Pi in a measurement or control project. It does not make Windows installers.
balenaEtcher
balena
Flashes OS images to USB drives and SD cards in three steps, with write verification and system drives hidden.
Get it from the vendorDisk cloning: Clonezilla boots from a USB stick and images a disk or clones disk to disk, including deployment to dozens of machines over a network; its text interface takes some learning.
Clonezilla
NCHC Free Software Labs
Disk and partition imaging and cloning from boot media, including deployment to dozens of machines at once over a network.
Get it from the vendorWindows itself includes Disk Cleanup and Storage Sense, which are enough for most users to clear temporary files and old updates.
Outdated and misleading advice you will find online
- CCleaner as a “strong free choice” — the free edition comes with upgrade prompts, usage-data collection and bundled offers in the installer, and in 2017 an infected version was distributed.
- dupeGuru as the top duplicate finder — its last release came out in July 2022. Czkawka replaces it.
- HDD Guardian, HD Tune, DriveDx and FSlint — still in lists, but marked as discontinued on AlternativeTo.
- Disk Space Scanner — on the MindGems list, but its latest version dates from 2000.
- “Free partition software” that is a trial — Acronis Disk Director, Hetman, BootIt (30 days), 4DDiG (7 days) and Active@ (21 days for some tools).
- The “free editions” of EaseUS, MiniTool and AOMEI — they top lists with sponsored slots, but their free limits are not clearly published, some key operations are locked and upgrade prompts are constant. Paragon Partition Manager CE is for non-commercial use only.
- “SpaceSniffer is abandoned” — so say older articles, but it has a new 2.x line on the official site. It still has no published licence terms for commercial use.
Which tool to choose, by need
The disk is full and you do not know why: on a personal PC, WizTree; on a work PC, WinDirStat (WizTree and TreeSize Free are not free for commercial use); on Linux, QDirStat or Filelight.
Clearing temporary and duplicate files: Windows Disk Cleanup first, BleachBit for caches and leftovers, Czkawka for copies of the same files across project folders.
Moving to a bigger SSD or changing partitions: Clonezilla to clone the disk, then GParted Live to grow the partition. Back up before any change.
Reinstalls and rescue drives: Rufus for a single Windows installer, Ventoy for one drive with several systems and rescue tools, balenaEtcher for a Raspberry Pi SD card.
Drive health: CrystalDiskInfo on a Windows PC, GSmartControl on Linux and macOS, and smartd on a server or NAS where you must know in advance that a disk is failing. CrystalDiskMark when the question is speed, not health.
Sources
- SoftPicker — 8 Best Free Disk Cleanup Tools in 2026
- StoredBits — Top 6 Best Disk Cleanup Software in 2026
- How-To Geek — Best free tools to analyze hard drive space on Windows
- MindGems — Top 7 Best Free Disk Space Analyzer Tools
- SoftwareTestingHelp — The 12 Best Free Disk Partition Software for Windows in 2026
- iTechGuides — Best Disk Partition Software in 2026
- Gitnux — Top 10 Best HDD Health Check Software of 2026
- AlternativeTo — CrystalDiskInfo alternatives
- AlternativeTo — dupeGuru alternatives
- AlternativeTo — GParted alternatives
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