Why Not Just Use Google Drive?

Google Drive comes with every Google account, shares its storage with Gmail and Google Photos [21], and lets several people edit the same document at once. Moving files somewhere else means new apps, new links to send and new habits. The usual argument for doing it, that your files are not encrypted, is not true: Google encrypts them.

The useful question is narrower. Encryption protects a file from someone who steals a disk or listens on the network. It does not say who else holds the key. In Google Drive that is Google, and almost everything that is convenient about Drive, and everything that is a privacy cost, follows from that one fact.

Safe from outsiders is not the same as private from Google

Google says every file uploaded to Drive, and every document made in Docs, Sheets and Slides, is encrypted in transit and at rest with AES-256 [1]. That is encryption at rest, and it does its job: a stolen hard drive from a Google data center gives the thief nothing readable.

The keys are Google’s. Google’s encryption whitepaper, which it says applies to consumer as well as business data, describes keys managed inside Google and states that each piece of stored data “can only be decrypted by authorized Google services and employees” [3]. That is key custody with the provider: Google’s own systems can open your files whenever they need to, and nothing in a personal account changes that.

So Google Drive is not insecure. A security question asks whether strangers can get at your files, and Google’s answer to that is strong. A privacy question asks what the company storing the files can do with them, and that answer is set by Google’s policies, not by the encryption.

What Google can do with your files

Google’s privacy policy says it collects the content you upload, naming “docs and spreadsheets you create”, and that “automated systems” analyze your content to provide features such as tailored search results and to detect “spam, malware, and illegal content” [4]. The same policy says Google does not show you personalized ads based on your Drive content.

The Drive terms add a second check by people as well as machines. Google “may review content to determine whether it is illegal or violates our Program Policies”, and may remove it [5]. The terms also say Google claims no ownership of your files and will not use them for marketing.

The third route is the law. Google shares information when it believes disclosure is necessary to respond to “legal process, or enforceable governmental request”, and reports how many requests it receives in its transparency report [4]. Because Google holds the keys, a valid order can reach the contents of your files, not only your account details.

Google does sell storage it cannot read, under the name client-side encryption. With it, Google says, “Google cannot decrypt your files” [1]. It is limited to the Frontline Plus, Enterprise Plus, Education Standard and Education Plus editions of Google Workspace [2], an administrator has to switch it on, and the person creating encrypted files must sign in with a work or school account [1]. A personal Google account, with or without a paid storage plan, cannot use it. The Google Drive review covers the rest, including file versions, AI features and the government request figures.

What Google holding the keys gives you

The same fact that lets Google read your files makes Drive easy to live with.

A forgotten password usually costs you no files. Google’s account recovery asks questions to confirm the account is yours and then lets you set a new password, and Google states there is no limit to the number of attempts [6]. Recovery can still fail if you cannot confirm the account, for example without access to its recovery phone or email; when it succeeds, your files are still there, because the key that opens them never depended on your password.

Google’s own help page shows what the server’s access is doing for you, by listing what stops working once Google cannot read a file. For files under client-side encryption, only one person can edit at a time; there are no comments on Drive files, no editing in the mobile app, no grammar check, translation or voice typing, and no file preview for Docs, Sheets or Slides [1]. Collaborative editing, previews and the tools that read your text all run on Google’s servers, and they need to see the document to do it.

If you use Dropbox instead

Dropbox works on the same model. Its security overview says Dropbox “manages file encryption on users’ behalf” and creates and stores the file keys inside its own infrastructure [8]. Its terms are blunter than Google’s: to provide search, thumbnails, previews and text recognition, “Dropbox accesses, stores, and scans Your Stuff”, a permission that extends to its affiliates and “trusted third parties” [7]. Dropbox’s privacy FAQ adds that it may build models “trained on your documents and metadata” for search, sorting and document summaries, and may look at “the content of their files” to choose users to market paid plans to [9].

End-to-end encryption exists at Dropbox only for teams, on the Business Plus, Advanced and Enterprise plans, and even there “metadata remains visible in plain text” [10]. Dropbox’s own list of what those encrypted folders lose reads like Google’s: no search indexing, no content search, no thumbnails, no previews, no shared links, no file requests [10]. Dropbox calls it “a downside on usability”, and that is an accurate description of the trade.

If you use iCloud Drive instead

iCloud Drive is the one mainstream service where a setting moves the keys to you. By default, which Apple calls standard data protection, the keys sit in Apple’s data centers, and Apple says it “can decrypt your data on your behalf”, for example after a forgotten password [11].

Advanced Data Protection changes that for iCloud Drive and other categories such as Photos and device backups. Apple calls it “an optional setting”; you turn it on from an iPhone, iPad or Mac, and doing so on one device turns it on for the whole account [12]. All your devices must run recent software, and managed and child accounts cannot use it. Once it is on, Apple no longer has the keys to help you recover: you get back in with a device passcode, a recovery contact or a 28-character recovery key [12].

It does not cover everything. Even with it on, Apple keeps under its own keys each file’s type, size, dates and checksums of the file content and name, and public “anyone with the link” sharing and collaboration in Pages, Numbers and Keynote put the keys back on Apple’s servers [11]. In the United Kingdom, Apple says it can no longer offer the setting to new users, and that UK users who already had it will be given time to switch it off to keep using iCloud; elsewhere it remains available [13]. If you are on Apple devices outside the UK, turning it on is the smallest step toward files the provider cannot read.

What private cloud storage costs you

Services built the other way, where files are encrypted on your device before upload and the provider never holds a readable key, are usually described as zero-knowledge storage. The reviews on this site cover Proton Drive, Filen, Tresorit, MEGA and Sync.com. Each of them pays for that design in ways you should know before switching.

Server-side features get thinner. A server that cannot read a file cannot index its text for search, render a preview of it or run an editor on it, which is exactly what Google’s and Dropbox’s lists above describe. The private services fill part of the gap on your device: some generate thumbnails before upload, and Proton describes its Proton Docs editor as “end-to-end encrypted, real-time collaborative” [15]. Others have none, or only through an editor whose server reads the file, and the reviews say which.

A lost password can mean lost files. When only you hold the key, nobody can hand it back. Proton’s support page says that with a password reset method but no data recovery method, “you’ll lose access to everything that was on your account before the password reset” [14]. Most services of this kind offer a recovery key or phrase, and it works only if you saved it before you needed it. Tresorit offers none: if you forget the password and are not signed in on any device, the only option is to reset the account, which deletes the files. Some soften this by keeping a copy of your key: Sync.com’s terms say that with email password reset enabled, Sync keeps your key in escrow and the account “is not configured on a strictly zero-knowledge basis” [16], and its help pages say the setting is on by default on paid plans.

“Zero-knowledge” is a design claim, and some designs have failed under testing. In 2024 cryptographers at ETH Zurich tested five end-to-end encrypted storage services against a server controlled by an attacker and found severe flaws in four of them; for Sync, they showed that a compromised server could read files uploaded after the attack and plant and alter files [17]. Sync has publicly confirmed a fix only for a leak through shared links. The same study found smaller weaknesses in Tresorit, described in its review. Earlier, in 2022 and 2023, researchers published attacks that let whoever controls MEGA’s servers recover a user’s private key [18]. MEGA says its March 2023 update closes these attacks; it has not said whether the root cause the researchers named, keys stored without a check that they have not been altered, is fixed. These are the risks the encryption is meant to remove, which is why the research matters more than a vendor’s description.

An audit the vendor ordered is not the same as an independent check. Proton says it “subjected” its Drive mobile apps “to an independent security audit by Securitum” [19]: the auditor is an outside firm, but Proton chose when, what and whom to test, and published the result itself. Filen has published no independent security audit and plans its next one after a rebuild of its backend that has no date yet [20]. Open client code, which Proton Drive, Filen and MEGA publish in some form, lets outsiders read how the apps encrypt; it does not replace a review of the whole system.

When Google Drive is genuinely fine

Google Drive is a reasonable choice, not a mistake, when:

• Your concern is strangers, not the company. Encryption in transit and on disk, plus two-factor authentication on the account, protects against a stolen disk or a guessed password.
• You work in shared documents every day. Several people editing at once, with comments, previews and spelling tools, is what Drive does best, and it needs Google’s servers to read the file.
• Losing access is your bigger risk than being read. A family archive kept by someone who will forget the password is safer where a provider can restore it.
• The files are not sensitive to Google: shared school or club documents, public material, things you would hand over anyway.

Reach for something else when you want

• Storage designed so that the provider cannot read your files or hand them over in readable form: Proton Drive, Filen or Tresorit, each with the costs above and in its review.
• To stay on Apple devices without changing service: iCloud Drive with Advanced Data Protection turned on, outside the UK.
• Encrypted file and folder names as well as content: all three private services above encrypt names; Filen also encrypts file sizes and types, Tresorit leaves top-level folder names readable.
• To keep editing documents with other people without the provider reading them: Proton Drive, whose editor Proton describes as end to end.

Whichever you pick, if it offers a recovery key or phrase, save it the day you sign up. With these services, that piece of paper is what stands between a forgotten password and an empty account.

Summary

Google Drive encrypts your files well against outsiders, and Google holds the keys. That lets Google analyze the content, review and remove files under its policies, and hand files over under legal process; it also lets Google restore your account, run real-time editing and show previews. Dropbox works the same way, with broader terms on scanning and model training. iCloud Drive is the exception among mainstream services: Advanced Data Protection moves the keys to your devices, if you turn it on and live outside the UK. Private services remove the provider from the list of readers, at the cost of thinner server features, a recovery key you must not lose, and designs that only some outside research has tested. If the only people you worry about are strangers, Drive with two-factor authentication is a defensible default.