Google has set a 2029 deadline to transition its security systems to post-quantum cryptography, calling the threat from advanced quantum computers urgent. This directly impacts Bitcoin and other cryptocurrencies, which rely on cryptographic signatures that quantum machines could break. Over $470 billion in Bitcoin is estimated to be in vulnerable addresses, underscoring the need for a coordinated, but slow, decentralized migration to new quantum-resistant standards.
Google has declared quantum computing a present danger and publicly committed to transitioning its entire infrastructure to post-quantum cryptography by 2029. The company stated quantum frontiers “may be closer than they appear,” citing rapid advances in hardware and compressed security timelines.
The announcement highlights two key threats, including “harvest now, decrypt later” attacks where data is stolen today for future decryption. It also warns that the digital signatures underpinning internet authentication, like those used in Bitcoin, will need replacement before a cryptographically relevant quantum computer arrives.
Bitcoin relies on elliptic curve cryptography, which a powerful quantum machine running Shor’s algorithm could theoretically break. According to estimates from Project Eleven, over 6.8 million Bitcoin, worth over $470 billion, sits in addresses vulnerable to such a future quantum attack.
Recent research has drastically reduced the estimated resources needed for quantum attacks. While earlier estimates suggested breaking Bitcoin’s encryption might require 20 million qubits, new analysis from Iceberg Quantum suggests it could fall to roughly 100,000.
Developers are beginning to prepare, with a proposal for a quantum-resistant address format recently merged into Bitcoin’s improvement repository. However, experts note that a decentralized migration of user funds could itself take five to 10 years to complete.
Jameson Lopp, co-founder of Casa, stated, “Right now, we’re several orders of magnitude away from having a cryptographically relevant quantum computer, at least as far as we know.” Google’s 2029 deadline creates external pressure for a network that cannot be upgraded by a single entity.
