How to live with a 256 GB MacBook without running out

Where 256 GB goes

You never have the full figure to yourself. macOS, its built-in apps and the working room it needs for swap, snapshots and updates take a share before you add a single file. What is left is shared between your apps, your files and everything apps store quietly in the Library folder.

Open System Settings, choose General, then Storage, and look at which rows are largest. On a small disk the same few things are responsible almost every time: Photos, Messages, a handful of large apps, developer files, and System Data.

Let iCloud hold the originals

If you pay for iCloud storage, two settings make the biggest difference on a small disk. Both keep everything visible on the Mac and download items when you open them. Both depend on having enough iCloud storage, and on an internet connection for files that are not local.

• Photos: open Photos, choose Settings, then iCloud, and select Optimize Mac Storage. Full-size originals stay in iCloud, and the Mac keeps smaller versions when space is short.
• iCloud Drive: open System Settings, click your name, then iCloud, then Drive, and turn on Optimize Mac Storage. Older files you have not opened recently are kept in iCloud only.
• Remember that iCloud is a sync service, not a backup. Deleting a photo or file on the Mac deletes it everywhere.

Move the big libraries to an external drive

A small external SSD is the most effective fix for a small internal disk. Things that are large and that you do not need every minute can live there.

• Photos library: quit Photos, drag Photos Library.photoslibrary from Pictures to a drive formatted as APFS or Mac OS Extended, hold Option while opening Photos and choose the moved library. Delete the original only after checking that the moved one opens and is complete.
• Video projects and footage: keep the current project on the Mac and archive finished ones.
• Virtual machines and disk images you use occasionally.
• Old project folders and archives.
• An external drive can fail or be lost. Anything that exists only there needs a second copy somewhere else.

Stop media from piling up

Streaming apps download more than you expect. In Storage, click the info button next to Music, TV or Podcasts to see and remove downloads. Anything you bought or subscribe to can be downloaded again.

In Podcasts, open Settings and turn on the option to remove played downloads. In Messages, open Settings, then General, and change Keep messages from Forever to One Year if you do not need older conversations on this Mac. That setting deletes old messages and their attachments, so save anything you care about first.

Remove large apps and sound libraries you do not use

In Storage, click the info button next to Applications and sort by size. Games, creative suites and development tools are the usual heavyweights. Removing an app you have not opened in a year costs nothing, since it can be installed again.

If you do not make music, the GarageBand sound library is worth checking. When Storage shows a Music Creation row, its info button lets you remove the library. Keep it if you use GarageBand, Logic Pro or MainStage.

Dragging an app to the Trash leaves its support files behind in the Library. For large apps those leftovers are worth removing too, either by hand or with an uninstaller.

If you write code on it

Development is where a 256 GB disk hurts most, because every tool keeps its own caches and build output. A few habits keep it under control.

• Delete node_modules and build folders in projects you are not working on. The install or build command recreates them.
• In Docker Desktop, open Settings, then Resources, and lower the disk usage limit so its disk image cannot grow past a size you choose.
• Remove simulators for devices and system versions you do not test on. The command below deletes only simulators that your installed Xcode can no longer run.
• Keep large AI models on an external drive, or remove the ones you are not using. They have to be downloaded again if you want them back.

xcrun simctl delete unavailable

A short routine that keeps it from filling again

Once the big items have a home elsewhere, a few minutes a month is enough: empty the Trash, sort Downloads by size and clear installers, and check the Storage screen for any row that has grown.

Keep a few tens of GB free at all times. macOS needs that room for swap and updates, and a nearly full disk is slower and more fragile than a nearly empty one.

Where Diskzy helps on a small disk

On a small disk the question is always what grew. Diskzy maps the whole disk and keeps the map current as files change, so you can see it without rescanning. System Data, explained names the parts of that category with their sizes.

The Clean up tab lists caches, logs, Xcode leftovers, project build folders, package-manager caches and old installers, each ticked or unticked with a reason, and Uninstall removes an app together with what it left behind. Everything goes to the Trash first. It is free for 72 hours, then $9 once for 2 Macs.