When importing video and audio into Premiere Pro, it processes versions of these files that it can readily access for faster performance. These are referred to as media cache files. These are stored in the Media Cache Files folder. In addition, there is a folder containing a database, which retains links to each of the media cache files. These are referred to as media cache database files. They are located in the Media Cache folder.
The Media Cache is where Premiere Pro stores accelerator files, including peak files (.pek) and conformed audio (.cfa) files. Clearing old or unused media cache files can help maintain optimal performance. Deleted cache files are recreated whenever source media requires them.
You can clear the Media Cache after you wrap up projects, which removes unnecessary preview render files and saves storage space.
In the Delete Media Cache Files dialog box that opens, you can choose to:
- Delete unused media cache files - Deleting unused media cache files removes files that were created for source media that can no longer be found.
- Delete all media cache files from the system - Deleting all media cache files deletes all cache files from the current location. Deleted cache files are recreated automatically whenever source media requires them. To remove all media cache files, restart Premiere Pro and select this option before opening any project.
Unable to open Premiere Pro?
With Premiere Pro closed, navigate to the location of these folders and delete the files manually. After you delete the files, then empty the trash.
Deleting the files manually with Premiere Pro closed deletes the current media cache files, as well, which is what you want to do when troubleshooting errors.
After deleting the files, you should see additional hard drive space become available. If you have older projects you have completed, it is a good idea to delete these files to save storage space and to keep your computer's hard drive tidier.
Keep in mind that a delay also occurs after you delete all cache files and then open a current project as the files need time to rebuild. If you have a large project, budget enough time for the media cache files to rebuild. This can be done overnight, for example.
For best performance, choose a fast SSD or NVME drive for your Media Cache - ideally a on a dedicated drive. You can change the locations of the media cache files by clicking Browse and navigating to the desired folder location. If needed, you can save the Media Cache on the same drive as your media.
You can set your preferences for the media cache using the following options:
- Do not delete cache files automatically - This setting is enabled by default in the Media Cache Preferences. Automatic deletion of media cache files applies only to .pek, .cfa and .ims files within the subdirectory folders Peak Files and Media Cache Files.
- Automatically delete cache files older than - The default value is 90 days. You can change it to a time period of your preference.
- Automatically delete oldest cache files when cache exceeds - The default is 10% of the volume size where the media cache is located.
When either the age or size preference is enabled, changes take place after quitting and restarting Premiere Pro. On the next application launch, Premiere Pro determines whether the media cache files meet the criteria for deletion, and if so, begins deletion 10 minutes after launch.
This housekeeping then occurs on a weekly basis from that point onward.