Insider Brief
- A new global competition backed by Project Eleven will award 1 Bitcoin—currently valued around $84,000 — to anyone who can use a quantum computer to break elliptic curve cryptography using Shor’s algorithm.
- Participants must submit a working quantum implementation targeting ECC keys up to 25 bits, with no classical shortcuts or hybrid methods allowed.
- The contest highlights the real-world cryptographic risks of advancing quantum hardware, as experts estimate a 256-bit ECC key could be cracked with 2,000 logical qubits, potentially within a decade.
A new competition is offering a single Bitcoin to anyone who can break elliptic curve cryptography using a quantum computer — no shortcuts allowed.
Launched by Project Eleven, an open science initiative focused on quantum and cryptographic challenges, the QDay Prize aims to test just how close quantum computing is to undermining one of the world’s most widely used encryption schemes. The contest runs through April 5, 2026.
Elliptic Curve Cryptography, or ECC, secures a wide range of systems — from Bitcoin wallets and secure websites to messaging apps and government infrastructure. Its appeal lies in efficiency: a 256-bit ECC key delivers the same protection as a much larger 3,072-bit RSA key. And while classical computers struggle to crack ECC, quantum computing presents a real threat, if it can be made to work.
Right now, a Bitcoin is worth about $84,000.
Pure Quantum Power
The challenge is simple in premise but formidable in execution: “Break the largest ECC key possible using Shor’s algorithm on a quantum computer,” according to Project Eleven. Submissions must demonstrate gate-level implementation of Shor’s algorithm solving the elliptic curve discrete logarithm problem (ECDLP): “No classical shortcuts. No hybrid tricks. Pure quantum power.”
Participants can register as individuals or teams, with no institutional affiliation required. Submissions must include quantum program code, a written explanation of the method, and details about the hardware used.
The quantum machine doesn’t need to be publicly available, but the organizers emphasize transparency, adding they will share submissions publicly.
The project has prepared a set of ECC keys ranging from 1 to 25 bits for testing. That’s well below the 256-bit keys used in actual Bitcoin wallets, but a successful attack — even at 3 bits — would mark a real milestone.
That’s because Shor’s algorithm, introduced in 1994, remains one of the most important theoretical breakthroughs in quantum computing. The algorithm allows a sufficiently large quantum computer to solve certain mathematical problems exponentially faster than any known classical method. Among them: factoring large integers and solving the ECDLP, which underpins ECC.
How Shor’s Algorithm Works
Shor’s algorithm works by turning the problem into one of finding the period of a mathematical function — a task quantum computers can solve efficiently using the Quantum Fourier Transform.
The algorithm creates a superposition of states, allowing it to explore many inputs at once and use interference to zero in on the correct answer. For elliptic curve cryptography, it targets the elliptic curve discrete logarithm problem, making it a powerful theoretical threat to modern encryption systems.
Error-Prone Quantum Systems
Practical implementation of Shor’s algorithm remains difficult. Today’s quantum systems are error-prone and limited in scale. Running Shor’s algorithm reliably requires high-fidelity qubits and error correction, both of which remain active areas of research.
“Today’s qubits have 99%–99.9% fidelity—is that good enough?” Project Eleven asks on the QDay Prize website.
Despite the limitations, quantum progress is accelerating. Companies and countries are advancing hardware steadily. Estimates suggest that around 2,000 logical (error-corrected) qubits may be enough to break a 256-bit ECC key, something researchers believe is achievable within the next decade.
That readiness has become a focus of international cryptographic communities. The U.S. National Institute of Standards and Technology (NIST) is already standardizing post-quantum algorithms, ones designed to resist quantum attacks. But until quantum systems are capable of breaking something real, no one knows exactly how urgent the threat is.
So far, no real-world ECC key has been broken by either classical or quantum methods. The best classical attacks remain exponentially slower than quantum ones in theory, and quantum demonstrations to date have only handled toy problems.
“Quantum computing is advancing fast, and the impact on cryptography is inevitable,” the organizers say. “Instead of waiting for breakthroughs to happen behind closed doors, we believe in facing this challenge head on, in a transparent and rigorous manner.”
