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Dropbox Smart Sync is now described in Dropbox Help as online-only files: their contents stay in Dropbox until you open them, while placeholders keep them visible in your computer’s Dropbox folder. This can reduce the space the Dropbox folder uses locally, but an online-only file needs an internet connection to download and open. Choose Make available offline for files you may need without connectivity.
What does Dropbox Smart Sync do?
Dropbox’s current help terminology is “online-only.” An online-only file’s contents are stored online rather than downloaded to your computer. Its name and a shortcut to Dropbox.com remain visible in the Dropbox folder as a placeholder. Dropbox Help says, “Online-only files won’t occupy storage on your local hard drive,” though the placeholder itself uses a small amount of local space. The full file downloads when you open it, so your device needs enough free space for that download. (Dropbox Help, “Free Up Space with Online-Only Files,” updated September 15, 2026.)
Which sync setting should you use?
| Setting | Visible in the local Dropbox folder? | Do contents use local storage? | Internet needed to open? | Scope |
|---|---|---|---|---|
| Online-only | Yes, as a placeholder | No local copy of the contents; the placeholder uses a small amount of space | Yes, to download and open | Individual files or folders |
| Available offline | Yes | Yes, a local copy is stored | No, once the item is available on the device | Individual files or folders |
| Selective sync | No, selected folders are removed from the computer’s file system | No local copy of the excluded folders | Yes, to access them through Dropbox online | Folders |
Use online-only when you want items to remain visible in the Dropbox folder but do not need their contents stored locally all the time. Use selective sync when entire folders do not need to appear on the computer. (Dropbox Help, “Free Up Space with Online-Only Files”; Dropbox Help, “How to manage team selective sync settings”.)
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How to make a file online-only or available offline
- Open the Dropbox folder on your desktop computer.
- Right-click the file or folder you want to change.
- Choose Make online-only to remove its locally stored contents while keeping a placeholder, or choose Make available offline to keep a local copy for offline access.
Dropbox also provides a sync preference for new files in the desktop app. The exact controls are in the app’s preferences; changing the default applies to new files within that preference’s scope and does not retroactively change existing items. (Dropbox Help, “Free Up Space with Online-Only Files”; Dropbox Help, “How to manage your Dropbox desktop app preferences,” updated September 29, 2026.)
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What happens when you open an online-only file?
Dropbox downloads the file to your computer when you open it. That download uses local storage; after opening, the item is no longer just an online-only placeholder. If you are short on disk space, check that the device can accommodate the file before opening it. To get access without an internet connection, make it available offline while you are connected.
Working offline
An online-only item cannot be opened from the computer’s Dropbox folder without an internet connection because its contents have not been downloaded. A file or folder marked available offline can be opened locally. Changes made while offline will not sync to other devices until the computer reconnects. (Dropbox Help, “How to make a file or folder available offline in Dropbox,” updated March 3, 2026.)
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How to tell which state a file is in
Check the item’s status in the Dropbox folder or its context menu: an online-only file is represented by a placeholder, while an available-offline file has its contents stored on the device. Dropbox’s exact appearance and interaction can vary on macOS, particularly for computers using the File Provider experience; follow the current guidance for your Mac rather than assuming all Finder setups behave identically. (Dropbox Help, “Free Up Space with Online-Only Files”; Dropbox Help, “How to open online-only files on macOS,” updated March 20, 2025.)
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- No internet connection: Connect to the internet, or use a copy you previously made available offline.
- Not enough disk space: Opening downloads the file. Free local space before trying again.
- Mac Finder behaves differently: Check Dropbox’s macOS instructions for your setup, including whether it uses File Provider.
Downloading a file from Dropbox through the website is a separate action from syncing it in the desktop Dropbox folder; Dropbox documents that process separately. (Dropbox Help, “How to open online-only files on macOS”; Dropbox Help, “How to download a file or folder from Dropbox,” updated February 16, 2026.)
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Platform, mobile, and team considerations
Desktop compatibility
Dropbox’s general online-only help page lists Windows 7 and higher and macOS 10.12 and higher as system requirements. Mac behavior depends on the Dropbox experience in use; Dropbox has separate guidance for its File Provider implementation, so those general requirements do not mean every Mac has identical Finder behavior. (Dropbox Help, “Free Up Space with Online-Only Files”; Dropbox Help, “How to open online-only files on macOS”.)
Mobile offline access
On mobile, Dropbox lets users mark files available offline. Folder-level offline availability is limited to certain paid plans; check the current Dropbox app and plan details for availability on your account. (Dropbox Help, “How to make a file or folder available offline in Dropbox”.)
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- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
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Team defaults
Dropbox says certain admins on Standard, Business, Advanced, Business Plus, and Enterprise plans can set online-only defaults for their team. Its admin guidance says this setting is not currently available to users with Dropbox for macOS on File Provider. Availability can depend on plan and platform. (Dropbox Help, “Set Dropbox to online-only for your team,” updated June 20, 2025.)
Frequently Asked Questions
What happens if I delete an online-only file?
Online-only describes where the file’s contents are stored, not a separate deletion rule. Deleting the item from the synced Dropbox folder is different from making it online-only; check Dropbox’s deletion guidance before removing a file you want to keep.
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Does online-only mean a file takes absolutely no space?
No. Dropbox says the placeholder uses a small amount of local space, although the file’s contents are not stored locally until downloaded.
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