If you are looking for a Proton Drive alternative, the short answer: Proton Drive is a sound zero-knowledge product, so switch only for a specific reason. The common ones are needing clients to upload documents to you without seeing a shared folder (Proton has no upload-only link), wanting a storage-only plan larger than Proton's 200 GB Drive Plus without a bundled suite, or wanting post-quantum encryption on stored files, which Proton has shipped in Mail but not in Drive. ShieldFive covers those three; Proton is ahead on audits, apps and breadth.
What Proton Drive does well
It is worth being clear up front: Proton Drive is a good product. Proton is a mature company with a real track record in privacy tooling, its apps are end-to-end encrypted and zero-knowledge, and its cryptography has been through external audits. Files are encrypted on your device before they reach Proton's servers, so Proton cannot read them. That is the right architecture, and Proton has shipped it for years.
It also comes with an ecosystem. Proton Mail, Proton VPN, and Proton Calendar share one account and one privacy posture, which is genuinely useful if you want encrypted mail, a VPN, and storage from a single vendor you already trust.
If that is what you are looking for, Proton Drive is a reasonable default. The rest of this page is about the specific cases where a different set of tradeoffs fits better.
Why people look for an alternative
People who already trust Proton still come looking for an alternative, usually for one of a few concrete reasons:
- Post-quantum protection on stored files. They want files encrypted today to stay confidential even against a future quantum computer, not only against present-day attackers.
- Collecting files from clients. Proton Drive has no upload-only link. A public link can let someone without an account upload, but it works like a shared folder: the uploader can also see what is already there. Firms that need clients to send documents privately need a request link instead.
- A storage-only plan. Proton's Drive-only plan is Drive Plus at 200 GB; beyond that, larger storage comes bundled with Mail, VPN and Pass in the Proton Unlimited and Duo plans.
- A focused storage product. They want a tool that does encrypted storage well, rather than a suite where storage is one component among several.
None of these are knocks on Proton. They are requirements Proton does not optimize for, and where a different product can.
ShieldFive: what it does, and its limits
ShieldFive encrypts every file, and its name, on your device before upload, on every plan including the free one. We store only ciphertext and never hold your keys. Sign-in sends a key derived from your password in the browser, not the password itself.
Web uploads default to post-quantum hybrid encryption (ML-KEM-1024 with XChaCha20-Poly1305), with AES-256-GCM as a fallback. The Android app, in Google Play testing and not yet a public release, uses the same format. There is no iOS app or desktop sync client yet. For firms, a document request lets a client upload files to you through one link, without creating an account.
The limits: we serve the web app's code, so the guarantee holds for the code you are served; file sizes and timestamps are not encrypted; the crypto core is open source (Apache-2.0) but the apps are not; and no external security audit has been completed. Review the security model and current plans before choosing.
ShieldFive vs Proton Drive at a glance
| Capability | ShieldFive | Proton Drive |
|---|---|---|
| Post-quantum on stored files | Hybrid default on web and Android, AES-GCM fallback | No (post-quantum ships in Proton Mail, not Drive storage) |
| Jurisdiction | EU | Switzerland (data in Switzerland and Germany) |
| Zero-knowledge / end-to-end | Yes — every file and filename, on every plan | Yes |
| Completed external audit | Not yet — pre-audit; crypto core is open to review | Yes — Securitum audit; ISO 27001, SOC 2 Type II |
| Product scope | Encrypted storage only | Suite: Mail, VPN, Calendar, Drive |
| Upload-only link for clients | Yes — document requests, client needs no account | No — public links let uploaders see the folder |
| Free tier | 5 GB | 5 GB |
| Apps | Web; Android in testing; no iOS or desktop sync | Web, Windows, macOS, iOS, Android |
Comparison reflects each vendor's public documentation as of 22 September 2026 and is updated as products change.
Where Proton is ahead, honestly
A fair comparison has to run both ways, so here is where Proton Drive is the stronger choice today.
Audits. Proton Drive has been through external security audits, including by Securitum, and Proton holds ISO 27001 and SOC 2 Type II. ShieldFive's crypto core is open and readable, but it has not yet completed a third-party audit — that audit is planned, not done. If an independent audit is a hard requirement right now, that is a real point in Proton's favour, and worth stating plainly rather than implying a parity that has not been earned.
Breadth. Proton is a suite. Mail, VPN, and Calendar come with the account, under one privacy posture and one bill. ShieldFive is storage only — it does encrypted file storage and sharing, and nothing else. If you want one vendor to cover mail, VPN, calendar, and storage together, Proton covers more ground.
If you need an audited, all-in-one privacy suite today, Proton is the stronger pick.
Which one fits you
Proton Drive fits you if you want a single, audited privacy suite — mail, VPN, calendar, and storage from one trusted vendor — and Swiss jurisdiction works for your requirements. It is mature, externally reviewed, and broad.
ShieldFive fits you if you want every file encrypted on your device by default without picking a special folder, need clients to upload to you without an account, and can accept a younger product with no external audit yet and no iOS or desktop sync app. Test it with files you can afford to lose first.
Try it
The free plan is 5 GB with no card. Upload a few test files, share one with an expiry, revoke it, and check recovery before moving anything that matters.
This comparison reflects each vendor's public documentation as of 22 September 2026; Proton's plans, free tier and sharing links were re-checked on 4 October 2026. It will be updated as the products change.