Quantum computers cannot break your website’s encryption today. That timeline is not indefinite, though. The real question for businesses building and maintaining web infrastructure is whether your systems will be ready for when the underlying math no longer holds.
Cloudflare just announced plans to operate a free public Certificate Authority designed specifically to issue quantum-safe TLS certificates. TLS, or Transport Layer Security, is the protocol that encrypts every connection between your users’ browsers and your server. It is what puts the padlock in the address bar. And the algorithms powering it right now, primarily RSA and elliptic-curve cryptography, were built without quantum computing as a realistic threat.
That is no longer a safe assumption.
Classical encryption relies on mathematical problems that are computationally hard for conventional hardware but far more manageable for a sufficiently powerful quantum machine using an approach called Shor’s algorithm. The cryptography community’s position is not whether this becomes a real-world attack vector but when. NIST, the National Institute of Standards and Technology in the U.S., has already ratified post-quantum algorithms including ML-DSA and Falcon that are designed to resist quantum attacks.
The problem is payload size. Direct substitution of post-quantum algorithms into traditional certificate chains inflates the cryptographic data in each HTTPS connection by roughly forty times. More data means more round trips, more latency, and more packet loss on constrained networks. You cannot just swap algorithms and ship it.
Cloudflare’s approach is Merkle Tree Certificates. Rather than signing each certificate individually with a heavy post-quantum signature, the system batches certificate issuances into a tree structure and signs only the root. Each certificate then carries a compact inclusion proof showing it belongs to that signed tree, which is logarithmically smaller than a full signature chain. Clients that support the new format receive the compact proof. Legacy clients fall back to the traditional certificate automatically. Nothing breaks during the transition.
The architecture also solves an audit problem. Logging and issuance happen as a single unified step, meaning certificates cannot enter circulation without a publicly transparent record. That matters for compliance teams and security operations that need auditable trails.
Cloudflare plans to make issuance free to all web properties, targeting broad public availability in early 2027 when Chrome’s quantum-resistant root store is expected to be ready. For DevOps and security teams, the preparation starts now. Certificate managers and automated renewal pipelines will need to handle the new format. Internal proxies, load balancers, and edge services will need library updates to support hybrid verification.
Companies that plan ahead will have a smoother transition, because the certificate management changes required are non-trivial and touch every layer of web infrastructure. Companies that wait will find themselves racing a deadline.
Want to explore how quantum-safe infrastructure could benefit your business? Let’s talk.