Current encryption standards — the protocols that protect your banking transactions, private messages, and sensitive files — are mathematically secure against classical computers. They are not secure against sufficiently powerful quantum computers. That distinction may sound abstract today, because quantum computers capable of breaking modern encryption do not yet exist at the required scale. But security experts broadly agree that the window to act is not as distant as most people assume, and the right time to upgrade your encryption is before the threat materializes, not after.
Post-quantum cryptography refers to a new generation of encryption algorithms specifically designed to remain secure even against quantum computing attacks. This guide covers practical steps you can take now, without specialized technical knowledge, to begin transitioning your personal security infrastructure to quantum-resistant standards.
Step 1: Understand Why This Matters Now
The most urgent reason to act now rather than waiting is a threat model called “harvest now, decrypt later.” Nation-state actors and well-resourced adversaries are believed to be currently collecting encrypted data — financial records, communications, government files — with the intention of decrypting it once quantum computers are capable enough to break current encryption.
For most personal users, the harvest-now risk is lower than it is for governments or corporations handling sensitive long-lived data. But the habit of updating your security posture proactively, rather than reactively, is a sound one regardless of your personal threat model. And for some categories of personal data — documents you expect to remain sensitive for a decade or more, long-lived cryptographic keys, secure communications with lasting legal or personal significance — the case for upgrading now is genuine.
Step 2: Inventory Your Current Encryption
Most people do not know what encryption their devices and services are using, which makes it impossible to assess what needs to change. A practical audit starts with the categories of encryption most relevant to personal users.
Messaging applications use end-to-end encryption protocols. The most common are based on the Signal Protocol, which is widely regarded as strong but not quantum-resistant in its current form. File storage encryption depends on your operating system and cloud provider. Secure shell (SSH) connections used by developers typically rely on RSA or elliptic curve cryptography — both of which are vulnerable to quantum attacks. Password managers use various encryption schemes depending on the provider.
For each category, identify what you currently use and check whether the provider has published a post-quantum roadmap. This does not need to be an exhaustive technical audit — a working knowledge of where your most sensitive data lives and how it is currently protected is sufficient to prioritize your next steps.
Step 3: Update Your Messaging Applications
Messaging is where most people’s most sensitive personal communications live, and it is also where the transition to quantum-resistant encryption is most accessible to non-technical users.
Signal has been actively developing and deploying post-quantum encryption extensions to its protocol. The PQXDH protocol — a hybrid approach that combines the existing Signal Protocol with a quantum-resistant key encapsulation algorithm — is available in Signal’s current releases and provides meaningful protection against harvest-now-decrypt-later attacks.
For other messaging applications, check the developer’s current encryption documentation. Look specifically for references to ML-KEM (formerly known as Kyber) or CRYSTALS-Kyber — these are the key encapsulation algorithms that NIST has standardized as part of its post-quantum cryptography initiative. Applications that have not yet published any post-quantum roadmap should be noted as lower-priority items for sensitive communications.
Step 4: For Developers — Upgrade Your SSH Keys
If you manage servers or use SSH for remote access, your SSH key infrastructure is likely using RSA or elliptic curve cryptography. Both are on the list of algorithms that will be vulnerable once quantum computers at sufficient scale exist.
NIST’s post-quantum cryptography standards, finalized in 2024, include signature algorithms designed as quantum-resistant replacements. Dilithium (now formally known as ML-DSA) and Falcon (ML-DSA variant) are the primary options for SSH key replacement. OpenSSH has added experimental support for these algorithms, and the ecosystem is actively developing.
Generate a new set of SSH keys using one of these algorithms and register the public keys on your servers alongside your existing keys. Do not remove your existing keys yet — compatibility varies across server configurations. Run both systems in parallel until quantum-resistant support is verified across your full setup.
Step 5: Enable Quantum-Safe Cloud Storage
Major cloud storage providers are increasingly offering quantum-resistant storage options. ProtonDrive has published documentation on its post-quantum encryption implementation. Apple’s iCloud Advanced Data Protection feature uses end-to-end encryption and Apple has publicly committed to post-quantum upgrades in its security roadmap.
Check your cloud storage provider’s current security settings for any quantum-safe options and enable them where available. If your provider has no post-quantum encryption offering and no published roadmap, consider it a factor in your next provider evaluation — particularly for data you intend to store for many years.
For the most sensitive long-lived data — estate documents, cryptographic key backups, legally significant records — the most robust option remains physical: an encrypted offline hardware drive that cannot be reached by any network-based attack, quantum or otherwise.
Step 6: Build Post-Quantum Habits, Not Just Post-Quantum Tools
The technology transition to post-quantum cryptography will take years to complete across the full ecosystem of applications and services. In the meantime, the habits that make your current security posture strong also apply to the quantum-resistant future: use strong, unique credentials for every service; keep software updated to receive security patches as providers implement new algorithms; review and revoke access permissions you no longer need; and treat any access to sensitive data as something worth monitoring.
Post-quantum encryption does not replace good security hygiene — it adds a layer on top of it. The most likely path to a security breach for a personal user in the near term remains weak passwords, phishing attacks, and unpatched software vulnerabilities rather than quantum decryption. Address the immediate risks and build quantum resistance into your infrastructure progressively as the tools become widely available.
