Reference

Google Drive

Google Drive is Google’s cloud storage for files and folders. On desktop, Drive for desktop can stream files (kept online-only and downloaded on demand) or mirror them (a full local copy), which determines how much disk space it uses.

Cloud & backupGeneral

Google Drive

Also known as: Google Drive storage, Drive for desktop, Google Drive stream vs mirror

Streaming keeps files online-only until opened
Mirroring keeps a full local copy on disk
Account storage is shared with Gmail and Google Photos

Stream vs mirror on desktop

The Drive for desktop app offers two modes. Stream files keeps everything in the cloud and downloads a file only when you open it, using little local space; you can right-click items and choose Available offline to pin the ones you need without a connection. Mirror files keeps a full local copy of selected folders synced both ways, which uses disk space equal to those files.

Streamed, online-only files appear in your Drive folder with a cloud status and download on first open, so a large Drive can be browsed without filling your disk.

How it affects disk space

In streaming mode, local usage is roughly the size of files you have opened or pinned offline, plus a cache — not your whole account. In mirror mode, every mirrored folder takes its full size on disk. Note that storage in your Google account is shared across Drive, Gmail, and Google Photos, so freeing one can free room for the others.

Related terms

Keep reading the reference.

Cloud & backupCloud syncCloud sync keeps a folder of files identical across your devices and an online account, so a change in one place appears everywhere. By default synced files usually exist both in the cloud and on each device, so syncing does not automatically save local space.General Cloud & backupLocal vs cloud storageLocal storage is the fixed physical space inside your device that holds files even offline. Cloud storage is online space on a provider’s servers that you reach over the internet. They are separate pools — adding cloud storage does not enlarge the device, and a full device can coexist with an empty cloud.General AndroidGoogle Photos storageSince June 1, 2021, photos and videos backed up to Google Photos count against the 15 GB of storage shared across your Google Account. The old free, unlimited “High quality” backup ended on that date.AndroidGeneral Cloud & backupDropboxDropbox is a cloud storage service that syncs files across your devices. With Selective Sync and online-only files, items can live in the cloud without using local disk space — they download on demand when you open them.General

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Storage cleanup helpers