Quantum Computing Competition Tests Bitcoin Security with 1 BTC Reward

TLDR

• Project Eleven launched “Q-Day Prize” offering 1 BTC to whoever cracks the largest Bitcoin elliptic curve cryptography key using Shor’s algorithm on a quantum computer
• Over 10 million Bitcoin addresses with exposed public keys could be at risk from quantum computing advances
• Participants have until April 5, 2026 to complete the challenge, with even small successes (like cracking a 3-bit key) considered newsworthy
• Current quantum computers can manage 105-156 qubits, while experts estimate 2,000 logical qubits would be needed to break a full 256-bit Bitcoin key
• Solutions like Quantum-Resistant Address Migration Protocol (QRAMP) and Coarse-Grained Boson Sampling (CGBS) have been proposed, but both require a hard fork

A quantum computing research firm has launched a competition to test Bitcoin’s vulnerability to quantum attacks. Project Eleven is offering 1 Bitcoin (currently valued at approximately $84,100) to any individual or team who can use a quantum computer to crack the largest portion of a Bitcoin cryptographic key.

The “Q-Day Prize” was announced on April 16, 2025, with participants having until April 5, 2026, to complete the challenge. The competition aims to assess how urgent the quantum threat is to Bitcoin and to encourage the development of quantum-proof solutions.

We just launched the Q-Day Prize.

1 BTC to the first team to break a toy version of Bitcoin’s cryptography using a quantum computer.

Deadline: April 5, 2026
Mission: Protect 6M BTC (over $500B)

— Project 11 (@qdayclock) April 16, 2025

The Quantum Threat

Project Eleven states that more than 10 million Bitcoin addresses have exposed public keys that could be vulnerable to quantum attacks. According to the firm, over 6 million Bitcoin—worth around $500 billion—could be at risk if quantum computers become powerful enough to crack elliptic curve cryptography (ECC) keys.

The challenge requires participants to run Shor’s algorithm on a quantum computer to break as many bits of a Bitcoin key as possible. This would serve as proof that the technique could eventually scale to crack a full 256-bit Bitcoin key once the necessary computing power becomes available.

“The mission: break the largest ECC key possible using Shor’s algorithm on a quantum computer. No classical shortcuts. No hybrid tricks. Pure quantum power,” Project Eleven explained on social media.

The firm emphasized that even cracking a 3-bit key would be considered major news. No ECC key used in real-world applications has ever been cracked using quantum methods.

Current State of Quantum Computing

Several online platforms currently offer quantum computing access, including Amazon Web Services and IBM. Current quantum computers are still far from the power needed to break Bitcoin’s cryptography.

IBM’s Heron chip can handle 156 qubits, while Google’s Willow manages 105 qubits. Experts estimate that around 2,000 logical qubits (error-corrected) would be enough to break a 256-bit ECC key.

Project Eleven believes a 2,000-qubit quantum system could be developed within the next decade. This timeline suggests that while the threat is real, there may still be time to implement solutions.

Bitcoin cypherpunk Jameson Lopp recently commented that the question of how concerned the industry should be about quantum computing is currently “unanswerable.” He noted, “I think it’s far from a crisis, but given the difficulty in changing Bitcoin it’s worth starting to seriously discuss.”

Proposed Solutions

The Bitcoin community is aware of the potential threat and is working on solutions. A Bitcoin Improvement Proposal (BIP) titled Quantum-Resistant Address Migration Protocol (QRAMP) was introduced in early April.

QRAMP suggests enforcing a network-wide migration to post-quantum cryptography to protect Bitcoin wallets. However, this would require a hard fork, which could be challenging to implement due to the need for community consensus.

Another approach comes from quantum startup BTQ, which has proposed a quantum-based alternative to Bitcoin’s Proof of Work called Coarse-Grained Boson Sampling (CGBS). This method uses quantum computing to generate unique patterns of photons, replacing traditional mining puzzles with quantum-based sampling tasks.

Like QRAMP, BTQ’s solution would also require a hard fork. The Bitcoin community’s appetite for such changes remains uncertain.

In February, Tether CEO Paolo Ardoino addressed the quantum computing concern. While acknowledging the threat is well-founded, Ardoino expressed confidence that quantum-proof Bitcoin addresses will be implemented well before any “serious threat” emerges.

The “Q-Day Prize” competition highlights the growing awareness of quantum computing’s potential impact on cryptocurrency security. By encouraging researchers to test the limits of current quantum technology against Bitcoin’s cryptography, Project Eleven hopes to better understand the timeline and urgency of implementing quantum-resistant solutions.