--- title: "Temporary files you can't see" url: https://storagestudio.us/wiki/temporary-files category: "Freeing up space" tags: ["free up space", "temporary files", "emergency space", "recycle vault"] summary: "macOS gives every app a hidden scratch area for temporary files. Sometimes an app leaves a lot behind there. Storage Studio finds those leftovers, groups them by the app that made them, and offers to clear only the ones nothing is using." updated: 2026-10-01T05:34:44.000Z --- # Temporary files you can't see macOS gives every app a hidden scratch area for temporary files. Sometimes an app leaves a lot behind there. Storage Studio finds those leftovers, groups them by the app that made them, and offers to clear only the ones nothing is using. Every Mac has a hidden scratch area where apps keep temporary files, plus a second hidden area for caches. It doesn't show up in Finder, and macOS clears it when you restart. Most of the time that's enough. But an app that makes temporary folders day after day, on a Mac that rarely restarts, can leave a lot behind there. Storage Studio looks in both areas and offers to **clear** what's safe to clear. ## Clear, not move Temporary files are meant to be thrown away: anything an app writes there is written knowing it can disappear. So Storage Studio never moves them to your external drive. It only offers to clear them, the same way macOS would on a restart. ## Where you'll see them Leftover temporary files appear in [Emergency Space](https://storagestudio.us/wiki/emergency-space) as rows such as **Clear the temporary files** *(app)* **left behind** or **Clear** *n* **folders of temporary files named** *(name)*. They're grouped by the name the folders share, so hundreds of folders from one app become a single row. Where Storage Studio can tell which installed app made them, it names the app. Where it can't, it shows the name as it found it rather than guessing. A group has to be at least 500 MB to be listed, and at most six groups are shown. The row explains what it found, for example how many days the folders have been piling up. If more were made today, it tells you that clearing them buys you room rather than fixing the cause: the lasting fix is in that app's own settings. ## What has to be true before anything is cleared Being in the scratch area only makes a folder a candidate. Each folder must also pass every one of these checks, or it's left alone: - It really is a folder directly inside one of the two temporary areas, not a shortcut leading somewhere else. - Nothing on your Mac has it open right now. - No app is running a service out of it. - Nothing inside it has changed in the last 6 hours. - A copy can be kept in the [Recycle Vault](https://storagestudio.us/wiki/recycle-vault), or the row tells you plainly that it can't. When some folders in a group fail a check, the row says how many it's offering and how many it's leaving alone, with the reason in plain words, for example *These were written to in the last few hours, so something is still using them.* ## Getting them back When there's room, a copy goes to your fast drive first: *A copy is kept on your fast drive, so you can put them back.* For a very large group the row warns that keeping the copy will take a while, and you can carry on working while it happens. Anything cleared this way is listed in the Recycle Vault, where you can put it back. See [Restoring something from the Recycle Vault](https://storagestudio.us/wiki/restoring-from-the-recycle-vault). See also: [Clearing app caches safely](https://storagestudio.us/wiki/app-caches) · [Why deleting files doesn't always give the space back](https://storagestudio.us/wiki/why-deleting-doesnt-free-space) · [Where did my space go?](https://storagestudio.us/wiki/where-did-my-space-go) · [Cache](https://storagestudio.us/wiki/glossary-cache) ## What links here - [Clearing app caches safely](https://storagestudio.us/wiki/app-caches) - [Emergency Space: when the disk is full right now](https://storagestudio.us/wiki/emergency-space) - [The Recycle Vault](https://storagestudio.us/wiki/recycle-vault)