If you edit video on a Mac, the Adobe Media Cache is one of the most aggressive hidden space consumers on the drive. It commonly grows to 50-150 GB.
Short answer: open Premiere Pro or After Effects, go to Settings > Media Cache, and delete all media cache files from the system. Adobe regenerates what a live project needs next time you open it.
Why the cache grows so fast
When you import 4K footage or complex audio, Adobe generates optimized helper files — audio peak files (.pek) and conformed video files (.cfa) — so timeline playback stays smooth.
Those helper files stay on the internal drive long after the project is closed. Adobe rarely removes them automatically.
Clearing the cache
- open Premiere Pro or After Effects (ideally with no project open)
- click Premiere Pro > Settings > Media Cache
- in the Media Cache Files section, click Delete...
- pick Delete all media cache files from the system
- confirm
Reopening an old project triggers a short rebuild of the cache for that specific project. No edits or source media are affected.
Preventing it from refilling
In the same Media Cache settings pane, enable Delete oldest cache files when cache exceeds and pick a cap that matches your drive — 20 GB on a small SSD, 50 GB on a larger working drive.
That alone stops the worst of the runaway growth.
Better next routes
If the drive is still full after clearing the cache, continue with How to Find Large Hidden Files on Mac.
For the broader cleanup framing, use What Is Purgeable Storage on Mac?.