What is “purgeable” space on a Mac - and how to reclaim it

What purgeable space is

Purgeable space is data macOS considers safe to remove on demand: local Time Machine snapshots, cached files, and files already uploaded to iCloud that can be re-downloaded. It counts as "used" until macOS decides to clear it - which it does on its own schedule, not yours.

The biggest culprit: local snapshots

When Time Machine can't reach its backup drive, macOS keeps hourly snapshots locally. These can quietly occupy many gigabytes. List them with:

tmutil listlocalsnapshots /

You can delete a snapshot by its timestamp with tmutil deletelocalsnapshots <date>, though the syntax is finicky and requires care.

Caches and iCloud-evictable files

Clearing app caches (~/Library/Caches) reclaims space immediately. Files stored in iCloud can be "removed download" to free local space while staying in the cloud.

Reclaim it without the guesswork

TidyBar finds local snapshots and caches that are eating your disk and thins them safely - turning "purgeable" space you can't control into free space you can, on your schedule. Everything removable goes to the Trash where applicable, and scanning is free.