Common questions about UltimaOS.
Common questions about UltimaOS, the post-quantum encrypted workspace built in the European Union.
A sovereign European web operating system: sixteen end-to-end encrypted applications (chat, mail, files, documents, spreadsheets, AI and more) sharing one private key, on EU-only infrastructure, with NIST-standardized post-quantum cryptography.
Individuals, families, clubs and associations, businesses, builders — anyone who values privacy, security, and European sovereignty over the convenience of surveillance-based free services.
During early access, UltimaOS is free for individuals and organizations. After early access, pricing will be per-seat with accessible family tiers and per-organization plans. There is no per-app add-on.
Signal and Proton are point solutions — chat, mail. UltimaOS is a full operating system: chat, mail, files, documents, spreadsheets, calendar, contacts, AI, all sharing one private key, all post-quantum, all in one workspace.
ML-DSA-65 (FIPS 204) for signatures, ML-KEM-768 (FIPS 203) for key encapsulation, XChaCha20-Poly1305 (RFC 8439) for symmetric encryption, HKDF-SHA256 for key derivation, Argon2id for passphrase hashing. No RSA, no elliptic-curve.
Yes. Every payload is encrypted in your browser. The server only ever stores ciphertext and public keys. We cannot read your data — by architecture, not by promise.
Sign in on a new device with your passphrase. The same private key is derived locally and your entire encrypted history becomes accessible. Lose your passphrase too? Three of your five recovery trustees can cooperatively regenerate your key.
We are a European company operating on EU infrastructure. The US CLOUD Act does not apply. Under EU law, we can only be compelled to disclose content we have technical access to — which is none, because the content is encrypted to your key.
Encrypted data, EU-only infrastructure, no advertising, no third-party trackers. The architecture is GDPR-compliant by design, not just by policy.
UltimaOS is a European company. The CLOUD Act does not apply. Your data cannot be obtained via a US subpoena.
We publish a quarterly transparency report listing every government request we received, our response, and aggregate operational metrics. Compliance is documented and verifiable.
Access is free during early access, invite-only. Request an invite through the contact form on this site and the team will respond within a few days. Organizations can request direct access for an extended pilot.
The whitepaper documents the cryptographic stack, the threat model, and the architecture. The post-quantum cryptography page explains the algorithms. The NIST standards (FIPS 203, 204) and IETF RFCs (8439) are referenced throughout.
On-premises and sovereign-cloud deployments are available for enterprise customers. The cryptographic architecture works the same way; only the server component changes. Contact enterprise@ultimaos.com for details.
Use the contact form on this site for general inquiries. For security disclosures, security@ultimaos.com. For privacy or DPO matters, dpo@ultimaos.com. For press, press@ultimaos.com.