Useful tip Mac (저장 공간 부족 시)

Freeing Up Space for the 18.4GB macOS 27 Installer: How to Safely Clear Mac System Cache

The macOS 27 Golden Gate installer weighs in at an unprecedented 18.4GB. Here is a step-by-step guide to reclaiming disk space safely using terminal commands and selective cache pruning.

Section
Tips
Applies to
Mac (저장 공간 부족 시)
Reviewed
2026-09-14

At a glance

macOS 27 requires at least 35GB to 40GB of free drive space to unpack and install its 18.4GB payload. Prune Xcode derived data, purge local user caches, and clear stale snapshots before upgrading.

One of the most frequent hurdles during annual macOS upgrades is the dreaded 'Not enough free space to install' warning.

The macOS 27 Golden Gate installer weighs 18.4GB. Accounting for archive extraction, APFS snapshot creation, and safety overhead, your Mac requires approximately 35GB to 40GB of contiguous storage.

Purging User Caches Safely

Stale application caches inside ~/Library/Caches frequently hoard tens of gigabytes. Execute the following terminal command to safely prune old transient data:

Terminal — Clear User Caches
rm -rf ~/Library/Caches/*

Clearing Xcode Derived Data

If you build or test applications on your Mac, lingering build artifacts can consume massive storage:

Terminal — Delete Derived Data
rm -rf ~/Library/Developer/Xcode/DerivedData/*
In this guide
  1. Purging User Caches Safely
  2. Clearing Xcode Derived Data
  3. At a glance
  4. Run the command
  5. How to use it
  6. Questions that usually follow
  7. Continue reading
  8. References

USAGE

How to use it

Run the command

Copy the command below and paste it into the terminal described in the guide.

Administrator terminal
rm -rf ~/Library/Caches/*

Questions that usually follow

Will clearing caches delete my personal files?

No, ~/Library/Caches contains only temporary runtime data; documents, photos, and project files remain untouched.

Can I use an external USB installer instead?

Yes, building a bootable installer on a 32GB USB drive using createinstallmedia minimizes internal disk overhead.

References