iCloud & iCloud Photos · Troubleshooting iCloud space
Why do my iCloud files download again after I made them online-only?
Short answer: Something opened them — any app reading an online-only file makes macOS download it again. Look for apps or backup tools that scan iCloud Drive. Storage Studio's own scans skip online-only files and don't download them.
Because something opened them. Any time an app reads an online-only file — you opening it, an app re-indexing a folder, a backup or sync tool reading every file — macOS downloads it again so the app can use it.
Common causes:
- An app that scans whole folders, such as a photo or media organiser, or backup software set to include iCloud Drive.
- A folder marked Keep Downloaded in Finder.
- Searching or previewing many files at once.
Storage Studio itself doesn't pull online-only files back: its duplicate finder skips online-only iCloud files, and its space measurements read file details without downloading content. If space keeps refilling, find which app is reading the folder and exclude iCloud Drive there.