Filelight vs baobab vs ncdu vs Storage Sifter

• The short version
• ncdu
• baobab (GNOME Disk Usage Analyzer)
• Filelight (KDE)
• Storage Sifter (ours)
• Also worth knowing
• What we would actually install

We make one of the tools in this comparison, so read it with that in mind. We have tried to be straight about where the others win, because a comparison that concludes "ours is best at everything" is worth nothing to you and we would not believe it either.

All four are free. Three are open source in the usual sense; all four cost nothing to try.

The short version#

ncdu#

Install it on every server you own. This is the one recommendation in this article we would make without hesitation.

ncdu is a terminal browser over du results. You navigate with arrow keys, it sorts by size, you drill into directories, and you can delete from inside it. It needs no graphics, so it works over SSH, in a recovery console, and on a machine with no desktop at all.

It is also the fastest to get an answer from on a headless box, because there is no alternative competing with it there.

Where it stops: it is a list. You read sizes and reason about them yourself. On a big unfamiliar filesystem, a visual layout genuinely finds things faster, because you spot a large rectangle you were not looking for. A list only shows you what you thought to open.

sudo ncdu -x /

(-x keeps it on one filesystem, which you almost always want.)

baobab (GNOME Disk Usage Analyzer)#

Already on most GNOME systems. Rings radiating out from the centre, one ring per directory level, sized by usage. Click a segment to zoom in.

It is dependable and unsurprising, and if it is already installed it is the correct first thing to open. It scans a home directory quickly and it integrates with the desktop's trash.

Where it stops: rings get hard to read past a few levels deep, thin slivers are awkward to click, and like Filelight it answers "how big is this" and stops there. No file classification, no advice.

Filelight (KDE)#

The same idea from the KDE side, and a bit quicker in practice. Integrates with Dolphin so you can open a folder straight from the map. If you are in Plasma, this is your already-installed option.

Same limitation: the map ends the conversation. It has shown you where the space is, and everything after that is your judgment.

Storage Sifter (ours)#

A squarified treemap: every file and folder is a rectangle sized by real on-disk usage. Rendered on the GPU (wgpu/Vulkan), so panning and the animated drill-down stay smooth on filesystems where a CPU-drawn map would crawl.

Two things it does that the others do not:

It colours cells by what a file is. Caches and build artifacts, media, applications and libraries, source code and projects each get their own colour. The practical effect is that you can read a drive before clicking anything: a large amber region is reclaimable, a large green region is probably irreplaceable.

It answers "can I delete this?" Right-click anything and you get a verdict, what the path actually is (a package cache, a build directory, personal media, credentials, installed software), and why. A built-in catalogue recognises dozens of common tool directories. Where there is a better way to reclaim the space than deleting the folder, it shows the exact command for your package manager, with one-click copy. It detects pacman, apt, dnf, zypper, apk, xbps, portage, and nix.

Safety: move to trash by default, tiered confirmation for permanent or out-of-home deletes, protected system roots refused outright, and it never deletes anything by itself.

Sizes come from real on-disk block counts, de-duplicate hard links, and stay on one filesystem, so the numbers answer "how much would I actually get back".

Where it is the wrong choice:

• On a server. It is a desktop application and it needs a GPU. Use ncdu.
• If baobab or Filelight is already installed and you only need one answer. Do not install something to learn one number.
• On very old or headless hardware, or in a VM without working GPU acceleration.
• If you want scriptable text output. Use du, or dust for something nicer to read.

It is Linux x86-64 only, free, MIT, and has no telemetry. AppImage, AUR (storagesifter-bin), or Cargo. Get it here.

Also worth knowing#

dust is du rewritten in Rust with a readable tree and bar chart. Excellent as a drop-in for the command you already type.

gdu is a faster ncdu, particularly on SSDs.

duf replaces df with something much easier to read. Different job (mount points, not file trees), but it belongs in the same toolbox.

What we would actually install#

• Laptop or desktop: whichever ring tool your desktop ships, plus Storage Sifter when you want to understand a drive rather than glance at it.
• Any server: ncdu, today, before you need it.
• Development machine: all of the above, and check docker system df first, because it is usually the answer.

And whichever you use, the sequence that saves the most time is in how to find what is using disk space on Linux: confirm which filesystem is full, clear the known caches, then go visual, and if the numbers refuse to add up, look for deleted-but-open files and snapshots.

We build Storage Sifter at Fopull LLC. If you think we have been unfair to another tool here, tell us on GitHub and we will fix it.