FileMayor vs GrandPerspective.
GrandPerspective is a beloved free Mac utility that visualises disk usage as a treemap. It is excellent at answering one question: where did my space go? FileMayor answers that question too — and then does something about it. The distinction matters: one is a diagnostic, the other is a full treatment.
The decision matrix.
| FileMayor | GrandPerspective | |
|---|---|---|
| Platforms | macOS · Windows · Linux · CLI · PWA | macOS only |
| Pricing | Free · Pro $19/mo · Team $99/mo | Free (donation-ware) |
| Primary function | Filesystem diagnosis + AI-planned organisation + rollback | Disk space visualisation (treemap) |
| Takes action | ✓ Move, rename, delete, organise | ✗ Visualise only |
| AI planning | ✓ Curative Triad — explain → cure → apply | ✗ |
| Rollback | ✓ Full session journal · undo --all | N/A — no actions taken |
| Duplicate detection | ✓ Content-hash deduplication | ✗ |
| CLI access | ✓ 14 commands, --json everywhere | ✗ |
| Disk visualisation | Text diagnosis (size, age, duplicates) | ✓ Interactive treemap |
| Watch mode | ✓ Yes (Pro) — real-time folder monitoring | ✗ |
| Best for | Finding the problem and fixing it, safely | Understanding where disk space is consumed |
You want a map. Nothing more.
GrandPerspective is free, fast, and makes a beautiful treemap. If you just want to understand the shape of your disk usage — not act on it — it is hard to beat. It has been around since 2005 and the codebase is solid. Some people open it, identify the large files manually, and delete them in Finder. That workflow is perfectly valid.
You want to fix it, not just see it.
FileMayor starts where GrandPerspective ends. Once FileMayor scans a directory, it does not just show you a chart — it explains what it found in plain language, proposes a structured cure (merge duplicates, archive old files, flatten unnecessary nesting), and applies the plan only after you approve it. Every single move is logged. If you change your mind, filemayor undo --all reverses the session completely.
FileMayor also runs on Windows and Linux — GrandPerspective is macOS-only — and detects content-level duplicates that a treemap view would never surface.
You found the problem. Now fix it.
The typical path: open GrandPerspective, see a 40 GB block labelled "Downloads", close it, and do nothing — because manually sorting thousands of files is worse than the original problem. FileMayor collapses that gap. Scan, read the diagnosis, approve the plan, done.
- →No manual file-by-file decisions — FileMayor proposes a complete plan you approve in one step.
- →Duplicate detection by content hash catches exact copies that different filenames hide from a treemap.
- →Runs on Windows and Linux — the same workflow wherever your files are.
Diagnosis and cure in one session.
GrandPerspective showed you that 40 GB block. Here is what FileMayor does with it.
$ filemayor scan ~/Downloads --top 10
Scanned 5,120 files · 38.7 GB
◆ Top space consumers
1. Videos/ 12.4 GB (32%) — 847 files
2. Installers/ 8.1 GB (21%) — 203 .dmg / .pkg / .exe
3. Duplicates 6.2 GB (16%) — 1,041 duplicate file pairs
◆ Proposed cure
[1] Archive 203 old installers to _archive/installers/ → saves 8.1 GB
[2] Deduplicate 1,041 pairs, keep newest → saves 6.2 GB
[3] Move 847 videos to ~/Movies/Downloads/
Estimated reclaim: 14.3 GB
Apply? [y/N] y
✓ 2,091 operations journaled. Run `filemayor undo --all` to reverse.FileMayor vs GrandPerspective — FAQ.
- Is FileMayor better than GrandPerspective?
- They do different jobs. GrandPerspective visualises disk usage as a treemap — it is excellent for understanding where your space went. FileMayor acts on that information: it scans a folder, proposes a structured cure (archive stale files, deduplicate, reorganise), and applies it with full rollback. GrandPerspective is a diagnostic. FileMayor is the treatment. Many people use both.
- Can FileMayor show disk usage like GrandPerspective?
- FileMayor surfaces disk usage in its diagnosis step — it reports total size, largest files, and wasted space from duplicates — but does not produce a treemap visualisation. If a visual treemap is what you need, GrandPerspective does it better. If you want to act on what you find, FileMayor is the right tool.
- What can FileMayor do that GrandPerspective cannot?
- FileMayor takes action. It can move, rename, archive, and deduplicate files. GrandPerspective only shows. Beyond that: FileMayor runs on Windows and Linux (GrandPerspective is macOS-only), exposes a full CLI, detects duplicate files by content hash (not just size), and logs every operation for full rollback.
- Do I need both GrandPerspective and FileMayor?
- Possibly, but often no. FileMayor's diagnosis step covers the same insight GrandPerspective provides — what is taking space, what is old, what is duplicated. If you only want a quick visual overview without taking action, GrandPerspective is free and fast. If you want to actually clean up, FileMayor handles discovery and action in one session.
- Is GrandPerspective still a good tool in 2025?
- Yes, for its specific purpose. GrandPerspective has been maintained since 2005 and the treemap is a genuinely useful way to see disk layout at a glance. It is free (donation-ware). It does not take action on files, and it is macOS-only — but for pure disk visualisation, it remains a strong choice.
GrandPerspective shows you the problem. FileMayor cures it. Use GrandPerspective when you just want a quick audit. Use FileMayor when you are ready to act.