Can I delete /private/var/folders?
/private/var/folders holds temporary files for macOS and your running apps. Here is why to leave it alone and what to do if it looks large.
Guides
Practical guides to Mac storage: what’s safe to delete and how to get the space back.
Articles, page 7
Mac keeps running out of space for no reason: 8 usual suspects
A disk that keeps refilling usually has a steady source: backups, downloads, caches, snapshots or a growing app. Here are eight to check.
macOS Tahoe System Data huge or stuck on 'Calculating'
A big System Data number or an endless 'Calculating' after a Tahoe update is common. Here is a calm checklist: wait, restart, check snapshots and caches, and leave system folders alone.
Do Mac cleaners work? An honest answer from people who build one
Some of what cleaners do is real and useful. Some of it you can do yourself in a few minutes. Here is how to tell the difference.
How to clear cache on Mac (and which caches to leave alone)
Clear known, rebuildable app caches one at a time after protecting offline or unsynced data; skip Apple, unknown and system folders.
System Data on Mac: what is inside and how to reduce it safely
System Data is not one folder. It is everything macOS cannot file under Apps, Documents or Photos. Here is what it usually holds, how to look at each part and what is safe to reduce.