Private Office Suites: Proton, CryptPad, ONLYOFFICE

Three models of privacy

Encrypted cloud (Proton Docs and Sheets, CryptPad). Documents are stored on the provider's servers, end-to-end encrypted so the provider can't read them, which makes real-time collaboration possible.
Desktop app (ONLYOFFICE Desktop Editors). Files are edited by a program installed on your computer. ONLYOFFICE also sells cloud and self-hosted servers.
On-device in the browser (Vault Studio Pro). Nothing is stored on a server. The file is processed in your browser tab, and encryption is applied when you export a .vault file.

Who each is for

Proton Docs and Sheets are part of Proton Drive, from Swiss company Proton AG. They suit people who already use Proton and want encrypted, shareable documents; Proton says it offers a HIPAA BAA to all its users. CryptPad, developed by XWiki SAS and licensed under the AGPL, suits groups who want an encrypted collaborative suite they can also host themselves, with accounts optional. ONLYOFFICE Desktop Editors, from Ascensio System SIA in Riga, suit people who want free, open-source desktop editors built around Office formats. Vault Studio Pro suits people working alone on sensitive files who want no account and no server copy.

Side by side

Vault Studio Pro compared with Proton Docs, CryptPad and ONLYOFFICE Desktop Editors
What	Proton Docs and Sheets	CryptPad	ONLYOFFICE Desktop	Vault Studio Pro
Where files are processed	Encrypted on Proton servers, edited in the browser	Encrypted on the CryptPad server you use, edited in the browser	Installed program on your computer	In your browser tab, on your device; no conversion server
Account	Proton account for the owner; shared links can allow editing	Optional; guest documents expire after 3 months without activity	None for the desktop app	None
Offline	Not documented for Docs	Not supported (prototype only)	Yes, as an installed app	Yes, after "Make available offline" (set up once while online)
Office formats	Docs imports and exports .docx; Sheets .xlsx and .csv; no presentations documented	.docx, .xlsx, .pptx (and OpenDocument) via its Document, Spreadsheet and Presentation apps	.docx, .xlsx, .pptx natively; OpenDocument; PDF editing and forms	.docx, .xlsx, .xls, .csv, .pptx, PDF, images
PDF redaction	Not documented	Not documented	Yes, since 9.1, including find-and-redact	Free; redacted pages rebuilt as images. No metadata removal or search-and-redact
Collaboration	Real-time, encrypted	Real-time, encrypted	Via ONLYOFFICE servers; E2E encryption in Workspace Private Rooms	None
Price	Free plan with 5 GB; paid Drive plans add storage	Free and open source; paid plans on cryptpad.fr	Free; DocSpace cloud Business from $20 per admin per month	Editors free; Pro $15/mo, $99/yr or $299 once

Choose one of the others if…

Proton: you want encrypted documents and spreadsheets that sync across devices and that you can edit together, from a provider that offers a BAA.
CryptPad: you want encrypted real-time collaboration, can self-host, or want to start without an account. Note that its spreadsheet app doesn't run OnlyOffice plugins or macros.
ONLYOFFICE: you can install software and want deep .docx, .xlsx and .pptx compatibility, XLOOKUP, JavaScript macros, a PDF editor with search-and-redact, or built-in AI assistants.

Choose Vault Studio Pro if…

You don't want your document stored on any server, even encrypted. Nothing is uploaded; see security.
You need no account and no install, on any computer with a browser.
You want one app for documents, spreadsheets, slides, PDF redaction and OCR, and password-encrypted .vault files (AES-256-GCM) for handoff.
You work offline on purpose, after enabling "Make available offline".

Limits of Vault Studio Pro to know first

No collaboration or sync. To share, you send a file.
Projects in the browser aren't encrypted at rest; only .vault exports and the File Safe are encrypted.
A .vault file can only be opened with Vault Studio Pro and the password.
No PDF metadata removal or search-and-redact yet; OCR is English only.
Not open source, not self-hostable, and no BAA.

Pro costs $9 for a one-off Week Pass, $15 a month, $99 a year or $299 once, and every Pro feature is unlocked for the first 7 days with no card. During the launch, a Founders plan costs $59 a year for as long as you renew (until 2026-12-01). See pricing, or the journalists' guide for an offline workflow.

Common questions

Which private office suite is best for collaboration?

Proton Docs and Sheets, and CryptPad, both offer end-to-end encrypted real-time collaboration. Vault Studio Pro has no collaboration features; it is built for working on a file alone on your device.

Is end-to-end encryption the same as processing on my device?

No. End-to-end encrypted services store an encrypted copy of your document on their servers, which lets you sync and share it. Vault Studio Pro stores nothing on a server: the file stays on your device, and encryption is used when you export a .vault file to send or store.

Which of these can redact a PDF?

ONLYOFFICE added redaction to its PDF editor in version 9.1, including find-and-redact. Vault Studio Pro includes free PDF redaction. We found no documented PDF redaction in Proton Drive or CryptPad.

More questions? See the full FAQ or contact us.

Sources (checked September 2026)

Proton, Proton Docs, Proton Sheets, Proton Drive, CryptPad, XWiki and ONLYOFFICE are trademarks of their respective owners. Vault Studio Pro is not affiliated with, endorsed by or sponsored by any of them; the names are used only to identify the products compared. Competitor details come from each vendor's own pages, checked in September 2026, and can change. If something here is out of date, email [email protected] and we will correct it.

Private office suites compared: Proton, CryptPad, ONLYOFFICE