DiskLens › How to check storage on Mac
How to Check Storage on Mac
New macOS moved everything twice, so here's where it lives now — plus two deeper ways when the built-in bar isn't enough.
Way 1 — The Storage bar (built in)
- Click the Apple menu → System Settings.
- Scroll the sidebar to General → Storage.
- Read the bar: gray = used, open = available. Hover the colored segments for category sizes; recommendations appear underneath.
Since macOS Ventura this replaced the old "About This Mac → Storage" tab. The recommendations (Empty Trash, Review Large Attachments, Store in iCloud) are genuinely useful — start there.
Way 2 — Finder folder sizes
Open any folder, press ⌘J (View → Show View Options), tick Calculate all sizes, then list view sorted by Size. Slow on big folders (Finder recomputes each browse) but built in.
Way 3 — A visual map (everything at once)
When you want the whole picture — every folder sized, the top 50 files named, duplicates flagged — drop a folder into DiskLens. It runs in the browser, installs nothing, uploads nothing, and the treemap makes the big blocks obvious in one glance.
Frequently asked questions
How do I check storage on my Mac?
System Settings → General → Storage shows the bar and categories. For folder detail use Finder’s Calculate-all-sizes or the DiskLens treemap.
Why does available space fluctuate?
Local Time Machine snapshots and purgeable space grow and shrink automatically; macOS reclaims them under pressure.