To clear the Adobe Media Cache, open Premiere Pro or After Effects, go to Settings › Media Cache, and delete all media cache files from the system; Adobe regenerates only what a live project needs the next time you open it. The Adobe Media Cache is one of the most aggressive hidden space consumers on a Mac, commonly growing to 50-150 GB as you edit.
TL;DR
- The Media Cache stores audio peak (.pek) and conformed video (.cfa) helper files.
- It commonly grows to 50-150 GB and Adobe rarely clears it automatically.
- Clear it via Premiere Pro / After Effects › Settings › Media Cache › Delete.
- Clearing the cache never affects your edits or original source media.
- Set a cache size cap so it stops refilling without limit.
Why does the Adobe Media Cache grow so fast?
The Adobe Media Cache is a folder of helper files Premiere Pro and After Effects generate so playback stays smooth. When you import 4K footage or complex audio, Adobe creates audio peak files (.pek) for waveform display and conformed video files (.cfa) for fast timeline scrubbing. These files speed up editing, but they remain on the internal drive long after the project is closed, and Adobe rarely removes them automatically. Across many projects, that backlog is what balloons to 50-150 GB and quietly fills a Mac's drive.
How do I clear the Adobe Media Cache? (step by step)
Clear the cache with no project open, if possible, so nothing is in active use:
- Open Premiere Pro or After Effects.
- Go to Premiere Pro › Settings › Media Cache (or After Effects › Settings › Media Cache on macOS; use Edit › Preferences › Media Cache on Windows).
- In the Media Cache Files section, click Delete...
- Choose Delete all media cache files from the system.
- Confirm.
Reopening an old project triggers a short rebuild of the cache for that specific project only. Your sequences, edits, and original source media are never touched.
How do I stop the cache from refilling?
In the same Media Cache settings pane, enable Delete oldest cache files when cache exceeds and set a cap that fits your drive, around 20 GB on a small SSD or 50 GB on a larger working drive. You can also move the cache to an external scratch drive via the Media Cache Files Location setting to keep it off the system disk. Together these stop the worst of the runaway growth without you having to clear it manually each time.
Is it safe to delete Adobe Media Cache files?
Yes, it is safe. The Media Cache contains only regenerated helper files (.pek and .cfa), not your project files, edits, or original footage. Deleting them with no project open is the cleanest approach; if a project is open, choose "Delete unused media cache files" instead so Adobe keeps what the live project still needs. After deletion, the only cost is a brief rebuild the next time you open each project.
When should you clear it versus look elsewhere?
Clear the Media Cache first whenever your editing drive is full and you have not purged it in a while, it is often the single largest reclaimable chunk. If the drive is still full afterward, the weight is likely elsewhere: exported renders, project archives, or system files. On a Mac, a large opaque "System Data" figure is a common next suspect. For that broader picture, see mysterious System Data on Mac and how to safely clean the disk.
FAQ
Will clearing the Adobe Media Cache delete my edits or footage?
No. The Media Cache holds only regenerated helper files (.pek and .cfa). Your sequences, edits, and original source media are untouched, and Adobe rebuilds the cache as needed when you reopen a project.
How big can the Adobe Media Cache get?
It commonly grows to 50-150 GB on an active editing machine, since Adobe rarely clears it automatically. Editors working in 4K or with many projects often see it grow even larger.
What are .cfa and .pek files in Premiere?
.cfa files are conformed video files for smooth timeline scrubbing, and .pek files store audio waveform peaks for fast display. Both are helper files that Adobe regenerates automatically, so they are safe to delete.
How do I stop the media cache from filling up again?
In Settings › Media Cache, enable "Delete oldest cache files when cache exceeds" and set a size cap that fits your drive. You can also relocate the cache to an external scratch drive to keep it off the system disk.
If your Mac is still tight on space after clearing the cache, work through mysterious System Data on Mac and deep-cleaning Windows without third-party utilities if you edit on a PC too. To shrink finished exports for sharing without re-rendering, the browser-based video compressor runs locally so nothing is uploaded; explore more under the storage cleanup helpers.
For your phone, Cleanor for iPhone finds large videos, duplicate photos, and heavy caches in one on-device pass — nothing uploaded.