Google Chrome Adopts Merkle Tree Certificates for Quantum-Safe HTTPS

HTTPS relies on public-key signatures and certificate chains to authenticate websites, but advances in quantum computing threaten to weaken today’s cryptographic foundations. Google Chrome is introducing Merkle Tree Certificates, or MTCs, which replace conventional signature chains with lightweight cryptographic proofs. The approach is designed to preserve connection performance while preparing the web’s trust infrastructure for post-quantum security.

Google plans to roll out the MTC initiative in three stages, gradually integrating the new certificate-verification model into Chrome and the broader HTTPS ecosystem. The main milestone is scheduled for 2027, when Chrome expects to establish a dedicated quantum-resistant root certificate store, known as CQRS. That repository would provide the trust foundation needed for wider deployment of post-quantum website certificates.