macOS process library
What is cloudd on Mac?
cloudd is the system daemon behind CloudKit, the service Apple’s apps and many third-party apps use to store and sync data in iCloud. When an app on your Mac sends or fetches iCloud data through CloudKit, cloudd does much of that work.
- Part of
- CloudKit, Apple’s iCloud data service for apps.
- Safe?
- Yes. It is part of macOS and handles iCloud data for apps.
- Can I quit it?
- You can, but macOS starts it again the next time an app syncs, so it rarely helps.
The short answer
A busy cloudd means something is syncing. After you sign in to iCloud, set up a new Mac, or turn on sync for a large library, it can run for hours. It settles once the backlog is done.
Normal use
What cloudd usually looks like.
Most of the time cloudd uses little CPU and a modest amount of memory, waking briefly when an app syncs a change.
After big changes it can stay busy for a while, often alongside related processes like bird and fileproviderd. Its activity in Activity Monitor’s Network tab rises with it.
Why cloudd uses so much CPU or memory
- A new Mac or a fresh iCloud sign-in
Apps download everything they keep in iCloud at once, which can take hours on a large account.
- Turning on sync for a big library
Enabling iCloud for an app with lots of existing data sends all of it up or pulls all of it down.
- Many apps syncing at the same time
Each app that uses CloudKit adds its own work, and cloudd handles it all.
- A slow or unreliable connection
Large transfers take longer on slow networks, so the work stretches out over a longer period.
How to calm cloudd down
Start at the top. Each step is more disruptive than the one before.
- Let it finish on good Wi-Fi
Keep your Mac awake, on power, and on a fast network until the sync catches up.
- See which apps use iCloud
Open System Settings, click your name at the top of the sidebar, then click iCloud to see which apps and features are syncing.
- Turn off sync for apps you don’t need
In that same iCloud list, turn off apps that don’t need to sync on this Mac. Their data stays in iCloud.
- Quit the app that’s syncing
If one app started a big sync, quitting it can pause the work until you reopen it.
- Restart
If cloudd stays busy with nothing new to sync, a restart clears a stuck session.
Seeing it in Spare
Find what it’s reacting to.
cloudd works on behalf of apps, so its spikes usually follow something you did in one of them. Spare groups each app with its helper processes, so you can see which apps were active while cloudd was busy.
Spare doesn’t monitor network traffic, so use Activity Monitor’s Network tab to see how much cloudd is transferring. Spare treats cloudd as a system task and never offers to stop it.
Common questions
About cloudd
Is cloudd a virus?
No. cloudd is part of macOS and backs CloudKit, the iCloud service apps use to sync data.
Why is cloudd using so much CPU?
It’s working through a sync. That’s most common after setting up a new Mac, signing in to iCloud, or turning on sync for a large library, and it eases off when the backlog is done.
Can I disable cloudd?
Not directly. Turning off iCloud sync for specific apps reduces its work. Signing out of iCloud stops it from syncing, but also turns off iCloud features.
Is cloudd the same as bird?
No. bird is tied to iCloud Drive, while cloudd backs CloudKit for apps. They often run together during big syncs.
Related processes
Sources: Apple: Store files in iCloud Drive on Mac, The Eclectic Light Company: iCloud Drive in Sonoma, FileProvider and eviction. Reviewed October 6, 2026.
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