It has been discovered by Google researchers that significantly fewer quantum resources are required to break RSA encryption, the same technology used to protect cryptocurrency wallets, than was previously believed.
Google’s quantum team recently published a research paper that alarmed Bitcoin enthusiasts by revealing a startling discovery. The team found that RSA encryption—used to secure assets like bank accounts and Bitcoin wallets—could be broken using only one-twentieth of the quantum resources previously estimated.
Google Quantum Researcher Craig Gidney emphasized the importance of understanding the cost of quantum attacks on vulnerable cryptosystems to plan a shift toward quantum-resistant cryptographic systems. In a 2019 study he co-authored with Ekerå, they estimated that a quantum computer with 20 million noisy qubits could factor 2048-bit RSA integers in eight hours. In the newly published paper, Gidney reported a significant reduction in the required qubit count.
Gidney argued that a quantum computer using fewer than one million noisy qubits could factor a 2048-bit RSA integer in under a week.
In an official blog post, the Google researcher stated that the latest finding represents a 20-fold reduction in the required number of qubits compared to their earlier estimate.
Why Quantum Computers Should Matter to Bitcoin Holders
However, experts do not expect such a development to occur in the immediate future. For perspective, IBM’s Condor, currently the most advanced quantum computer, operates with 1,121 qubits, while Google’s Sycamore functions using only 53 qubits. As a result, cryptocurrency holdings remain secure—for the time being. Nevertheless, it is the technological trajectory that raises concern, suggesting a direction that should prompt heightened awareness among crypto asset holders.
Google attributes the advancement to two key factors: improved algorithms and enhanced error correction techniques. Researchers discovered a method to perform modular exponentiation—central to encryption—at twice the previous speed. They also improved error correction by introducing an additional layer that tripled logical qubit density, allowing more effective quantum operations within the same physical qubit space.
Researchers also implemented a technique called “magic state cultivation,” which enhances the strength and reliability of special quantum components known as T states. This approach enables quantum computers to execute complex operations with greater efficiency while minimizing the consumption of additional resources, ultimately reducing the workspace required for fundamental quantum processes.
Bitcoin’s security relies on elliptic curve cryptography, which uses mathematical principles similar to RSA. If quantum computers compromise RSA sooner than expected, they may also accelerate Bitcoin’s vulnerability timeline. Although the cryptocurrency utilizes 256-bit encryption, which is more robust than the RSA keys examined by Google, the advantage is not as substantial as one might expect—particularly in the context of exponentially advancing quantum capabilities.
Experts are already exploring methods to use quantum technology to potentially compromise Bitcoin’s security.
Why Quantum Computers Should Matter to Bitcoin Holders
A quantum computing research initiative known as Project 11 introduced a Bitcoin bounty valued at nearly $85,000 for individuals capable of breaking even a simplified form of Bitcoin’s encryption through the use of a quantum computer. The challenge involves testing encryption keys ranging from 1 to 25 bits—a small fraction of Bitcoin’s 256-bit encryption—but the purpose is to monitor advancements in quantum decryption capabilities.
Project 11, while announcing their challenge, stated that Bitcoin’s security depends on elliptic curve cryptography. They warned that quantum computers running Shor’s algorithm will eventually break this encryption. The initiative aims to evaluate how urgent this potential threat is.
The broader security consequences go well beyond cryptocurrency. RSA and comparable encryption systems form the foundation of secure communications worldwide, encompassing sectors such as banking and digital authentication. Google highlighted that potential adversaries may already be collecting encrypted data to decrypt it later when quantum computing becomes viable. In response, experts are actively preparing to address this emerging threat.
Google stated that it has already encrypted traffic within Chrome and internal systems. The company implemented the standardized version of ML-KEM as soon as it became available.
Why Quantum Computers Should Matter to Bitcoin Holders
The National Institute of Standards and Technology (NIST) issued post-quantum cryptography standards last year and recommended phasing out vulnerable systems after 2030. However, Google’s latest research suggests that the industry may need to accelerate this timeline.
IBM has outlined plans to develop a 100,000-qubit quantum computer by 2033, working in collaboration with the University of Tokyo and the University of Chicago. Meanwhile, Quantinuum has set a goal to introduce a fully fault-tolerant quantum computer by 2029. In light of Google’s recent discoveries, these timelines have gained increased relevance and urgency.
Another critical factor involves determining how long quantum machines can operate without disruption. Google’s theoretical million-qubit system would need to function continuously for several days, sustain very low error rates, and execute billions of operations in a highly coordinated manner. Currently, quantum computers maintain coherence for only a few minutes, so there is no immediate cause for alarm.
The quantum threat hasn’t yet become imminent, but it is advancing more rapidly than experts initially anticipated. In response, the crypto community has already started developing quantum-resistant solutions. Solana developers introduced a quantum-secure vault that uses hash-based signatures, and Ethereum co-founder Vitalik Buterin suggested forking existing blockchain codebases as a safeguard against future quantum vulnerabilities.
Experts increasingly believe that developers will implement an anti-quantum hard fork in the future—ideally long before any successful quantum-based breach compromises the Bitcoin blockchain.
