Sync and cloud storage

*.icloud.com

Hosts under icloud.com run Apple's iCloud services. Apple lists the whole domain on port 443, and several hosts under it for specific jobs.

Run by ApplePorts: 443 TCPChecked: 1 November 2026

Short answer

Apple's iCloud domain. Apple lists *.icloud.com for iCloud services; specific hosts under it have their own pages.

Don’t block

Don't block the whole domain. Most iCloud services run under it, so iCloud sync, Private Relay and more stop.

Matches
*.icloud.com icloud.com

A name with *. covers every name under it: *.push.apple.com matches 1-courier.push.apple.com.

What it serves

Apple's enterprise host list names *.icloud.com in its iCloud section, for iCloud services. Devices also need Apple's Apple Account hosts to use iCloud.

Hosts under it with their own entries: gateway.icloud.com for CloudKit content, mask.icloud.com for Private Relay, probe.icloud.com for connection tests and metrics.icloud.com for diagnostics.

Kilobat matches the most specific entry first, so a connection to gateway.icloud.com shows that page, not this one.

Processes that use it

clouddPart of macOS. It syncs the iCloud data of apps that use CloudKit, so its traffic belongs to those apps.Process →birdPart of macOS. It runs iCloud Drive, so its traffic is your iCloud Drive files going up and down.Process →cloudphotodPart of macOS. It does all iCloud Photos sync, so its traffic is your photos and videos going up and down.Process →siriactionsdPart of macOS. It runs and syncs the shortcuts you make in the Shortcuts app, so iCloud sync of shortcuts can show under it.Process →

What breaks if you block it

Don’t block

Don't block the whole domain. Most iCloud services run under it, so iCloud sync, Private Relay and more stop.

What breaks if you block it

  • iCloud Drive, iCloud Photos and app data in iCloud may stop syncing.
  • iCloud Private Relay and other iCloud features stop.

With Kilobat Pro and the network filter, you can block a host for every app or for one app: in Connections, select a connection and choose Block. Apple’s own services are never blocked by Kilobat’s Protection lists.

Notes

Apple also lists *.icloud.com.cn and *.apzones.com for iCloud services in China.

Apple’s rules for its hosts

Apple’s list, Use Apple products on enterprise networks, says that devices open these connections, not Apple’s servers. Apple services fail any connection that uses HTTPS interception, so a proxy that inspects TLS should leave Apple’s hosts alone.

If a firewall allows hosts by name, allowing *.apple.com covers most Apple services, Apple says. A firewall that works only with addresses can allow 17.0.0.0/8 for IPv4, and 2403:300::/32, 2620:149::/32 and 2a01:b740::/32 for IPv6.

To see which app on your Mac opened a connection to this host, use Kilobat’s Connections tab, or the agent network log for AI agents.

Sources

Checked on 1 November 2026.