In a significant milestone for the field of quantum computing, Project Eleven has awarded its 1 Bitcoin “Q-Day Prize,” valued at approximately $78,000, to researcher Giancarlo Lelli for successfully cracking a 15-bit elliptic curve cryptography (ECC) key using publicly accessible quantum hardware. This breakthrough marks the largest public demonstration of a quantum attack on ECC to date, which serves as the foundation for the digital signatures utilized by cryptocurrencies such as Bitcoin and Ethereum.
Lelli’s work utilized a variant of Shor’s algorithm and was conducted on a quantum computer with about 70 qubits, capable of existing in multiple states simultaneously. The attack, which processed within mere minutes, involved a problem with 32,767 possible values—an impressive leap from previous public demonstrations that had tackled considerably smaller challenges. Although the 15-bit key is significantly smaller than the 256-bit keys that safeguard actual Bitcoin wallets, this achievement underscores the potential threat posed by quantum computing to cryptographic security.
Project Eleven’s CEO, Alex Pruden, emphasized the importance of this progress, noting that while modern Bitcoin security remains safe for now, advancements in quantum computing could bring “Q-Day”—the hypothetical day when quantum computers can break current cryptography—closer than previously thought. He remarked on the unpredictability of how quickly advancements could occur and the challenge of anticipating these changes.
Launched in 2025, the Q-Day Prize aims to challenge the notion that existing quantum systems can only perform trivial computations. By successfully cracking a 15-bit key, Lelli has demonstrated tangible progress in the field, shifting perceptions about the capabilities of current quantum technologies.
As major players in the quantum space, like Google, outline ambitious roadmaps, the notion of impending threats to cryptocurrencies grows. Google has projected a 2029 timeline for transitioning its systems to post-quantum cryptography, bolstered by their own advancements in quantum computing. Meanwhile, emerging research suggests that breaking Bitcoin could be feasible with as few as 10,000 to 20,000 physical qubits, further solidifying the urgency of addressing these vulnerabilities.
Pruden also highlighted the role that artificial intelligence may play in speeding up the timeline toward Q-Day, suggesting that AI could enhance quantum error correction and help attackers pinpoint weaker cryptographic targets. As researchers continue to refine their approaches, discussions are ongoing within the Bitcoin development community regarding potential solutions. Proposals such as BIP-360 and BIP-361 focus on introducing quantum-resistant transaction formats and phasing out outdated signature schemes to protect assets against future quantum threats.
While some experts remain cautious about the immediacy of the quantum threat, labeling it as a long-term engineering challenge, the discussions around these vulnerabilities remain active. The Ethereum Foundation is also taking steps toward post-quantum security, with co-founder Vitalik Buterin laying out plans to evolve Ethereum’s cryptographic framework.
As developments in both quantum computing and cryptographic defenses evolve, the implications for the cryptocurrency landscape continue to unfold, stressing the need for strategic foresight in the face of rapidly advancing technology.


