TLDR
- Project Eleven offers 1 Bitcoin to whoever cracks the largest Bitcoin 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
- The competition runs until April 5, 2026, aiming to benchmark the current quantum threat to Bitcoin
- Current quantum computers have 105-156 qubits, while breaking a 256-bit ECC key would require around 2,000 qubits
- Solutions like QRAMP and CGBS have been proposed but would require a hard fork of the Bitcoin network
A new competition has launched to test how vulnerable Bitcoin might be to quantum computing attacks. Quantum computing research firm Project Eleven is offering 1 Bitcoin (currently worth around $84,100) to whoever can crack the largest Bitcoin key using Shor’s algorithm on a quantum computer within the next year.
The competition, called the “Q-Day Prize,” was announced on April 16, 2025. It aims to measure the real-world threat that quantum computing poses to Bitcoin’s security. Project Eleven wants to know how urgent the threat is and to help find quantum-proof solutions.
“10 million+ addresses have exposed public keys. Quantum computing is steadily progressing. Nobody has rigorously benchmarked this threat yet,” Project Eleven wrote on X.
The stakes are high. More than 6 million Bitcoin, worth approximately $500 billion, could be at risk if quantum computers become powerful enough to crack elliptic curve cryptography (ECC) keys.
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
How the Competition Works
Participants can enter as individuals or teams. They have until April 5, 2026, to complete the challenge. The goal is to run Shor’s algorithm on a quantum computer to break as many bits of a Bitcoin key as possible.
This would serve as a proof-of-concept that the technique could eventually scale to crack a full 256-bit Bitcoin key. Project Eleven emphasized that contestants don’t need to break a full Bitcoin key to win.
“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 stated.
Even cracking a 3-bit key using pure quantum methods would be a major achievement. No ECC key used in real-world applications has ever been cracked using quantum computing.
Several platforms offer quantum computing access for contestants. These include Amazon Web Services and IBM. IBM’s Heron chip and Google’s Willow currently handle 156 and 105 qubits respectively.
The Future Quantum Threat
Experts estimate that around 2,000 logical qubits would be enough to break a 256-bit ECC key. Project Eleven believes such a system could be developed within the next decade.
Bitcoin cypherpunk Jameson Lopp recently commented on the quantum threat. “I think it’s far from a crisis, but given the difficulty in changing Bitcoin it’s worth starting to seriously discuss,” Lopp said in March.
Tether CEO Paolo Ardoino shares similar views. In February, he acknowledged the concern but expressed confidence that quantum-proof Bitcoin addresses would be implemented before any “serious threat” emerges.
The Bitcoin community is already working on potential solutions. A Bitcoin Improvement Proposal titled Quantum-Resistant Address Migration Protocol (QRAMP) was introduced in early April.
QRAMP suggests enforcing a network-wide migration to post-quantum cryptography. This would protect Bitcoin wallets but would require a hard fork of the network.
Another proposal comes from quantum startup BTQ. They’ve developed a quantum-based alternative to Bitcoin’s Proof of Work called Coarse-Grained Boson Sampling (CGBS).
CGBS uses quantum computing to generate unique patterns of photons. These would replace traditional mining puzzles with quantum-based sampling tasks. Like QRAMP, this solution would also require a hard fork.
The Q-Day Prize aims to gather concrete data about the current state of quantum threats. By incentivizing researchers to test real-world attacks, Project Eleven hopes to move beyond theoretical discussions.
Participants interested in the competition can register now. The winner will not only receive 1 Bitcoin but could also “go down in cryptography history,” according to Project Eleven.
