Chapter 06Built-in tools only
Photos and videos: the library, handled gently
A Photos library is the biggest thing on most Macs and the one people are most afraid to touch. Managed category by category, it is neither dangerous nor difficult.
Memories are not clutter. That is why this chapter is deliberately conservative: it removes duplicates, accidents and screenshots while protecting originals. The order matters, so work through the sections rather than jumping to the biggest number.
Start with Recently Deleted
Photos never removes an item immediately. Deleted pictures and videos wait in a Recently Deleted album for thirty days, and their full size still counts against your disk. Open Photos, find Recently Deleted under the sidebar, and clear it once you are sure the items inside are not wanted. On a library that has been cleaned before, this alone can return several gigabytes.
Find duplicates
- Open the Duplicates albumIn Photos, look for Utilities > Duplicates. macOS builds this automatically by comparing visual similarity, not file names.
- Review each setPhotos shows the copies side by side and marks the one it suggests keeping, usually the highest quality.
- MergeChoose Merge to keep one copy and discard the rest, or go set by set if you prefer control.
- Empty Recently Deleted afterwardsMerged copies land in Recently Deleted and only release their space once cleared.
Deal with screenshots
Screenshots accumulate without anyone deciding to keep them. In the Photos sidebar, open Media Types > Screenshots and sort by date. A screenshot is usually disposable once its information has been used or transcribed. This is safe, fast work; the only risk is deleting a screenshot you actually rely on, so glance before you sweep.
Find the large videos
Video dominates library size. A few minutes of 4K footage can outweigh thousands of photographs. Open Media Types > Videos and scan for the longest clips, especially screen recordings made by mistake and slow-motion footage captured in a pocket. If you cannot bear to delete a clip, export it to an external drive first, then remove it from the library.
Export before you archive
Photos can write originals out to a folder or an external drive: select items, choose File > Export > Export Unmodified Original, and pick a destination. Once the export is verified, delete the same items from Photos and clear Recently Deleted. This is the approved path for moving a large video library off a small SSD without losing anything.
Do not delete files inside the Photos library package by hand, and do not disable iCloud Photos while offline. Both can desynchronise the library in ways that are tedious to repair.
A tidy-library routine
| Step | Action | Typical saving |
|---|---|---|
| 1 | Clear Recently Deleted | 1–10 GB |
| 2 | Merge duplicates | 2–20 GB |
| 3 | Remove screenshots | 0.5–5 GB |
| 4 | Export and delete large videos | 10–100 GB |
| 5 | Turn on Optimize Mac Storage | Variable, often large |
Run this routine twice a year and a Photos library stays roughly the size of the memories it contains, rather than the size of everything you ever pointed a camera at.
Prefer the whole method in one file?
The Mactria Help e-book collects every chapter of this guide into a single, printable PDF with checklists, safe-deletion rules and a 30-minute cleanup routine.