Is Quantum Computing a Threat to Bitcoin? You Can Get Paid to Break Its Encryption

A quantum computing breakthrough could one day undermine the cryptography that secures the Bitcoin blockchain and its nearly $1.7 trillion worth of assets. Now, a BTC bounty is putting that threat to the test.

On Wednesday, quantum computing research group Project 11 announced a prize of 1 BTC—currently worth nearly $85,000—for the first team to break a simplified version of Bitcoin’s elliptic curve cryptography, or ECC, using a quantum computer.

“Bitcoin’s security relies on elliptic curve cryptography. Quantum computers running Shor’s algorithm will eventually break it,” Project 11 wrote on X. “We’re testing how urgent the threat is.”

The QDay Prize runs until April 5, 2026, and is open to both individuals and teams.

Founded in 2024 by Alex Pruden and Conor Deegan, Project 11 researches the intersection of quantum computing and cryptography, with a focus on the risks these technologies pose to blockchain systems.

Project 11 has prepared a set of ECC keys ranging from 1 to 25 bits. Teams must demonstrate their solutions using a key of the targeted length—for example, by cracking a 4-bit key if aiming for that level. It’s a small fraction of Bitcoin’s existing 256-bit encryption.

Elliptic curve cryptography is widely used in blockchain for its efficiency and security, but experts warn that quantum computing could undermine it by breaking the computational asymmetry that keeps it secure. And if someone were able to crack Bitcoin’s cryptography, then they could potentially walk away with well more than the contest’s 1 BTC prize.

“This is not a challenge to ‘break’ Bitcoin,” Pruden wrote on X. “There is already an enormous incentive for anyone with a quantum computer to use it to forge a signature and therefore steal funds from an address with exposed public keys.”

A quantum computer uses the principles of quantum mechanics to solve problems far beyond the capabilities of traditional computers, posing a threat to Bitcoin by potentially cracking the encryption that protects users’ private keys.

Adding to this fear is that, unlike high-powered supercomputers, which would take eons to crack Bitcoin’s encryption, a quantum computer could theoretically do it in minutes.

Blockchain developers on other networks are also working to prepare for a quantum future. In January, Solana developers introduced a quantum-resistant solution called Solana Winternitz Vault that uses hash-based signatures to generate new keys for each transaction, protecting user funds from potential quantum attacks. In March 2024, Ethereum co-founder Vitalik Buterin proposed a hard fork to protect Ethereum from similar quantum threats.

“While we believe this hasn’t happened yet, we also don’t really know how far away we are,” Pruden continued. “To prepare, we need a plan. And to develop a plan, we need the facts.”

While the challenge focuses on a dramatically scaled-down version of Bitcoin’s encryption, Project 11 sees it as a critical signal of what’s to come.

“This is only the start—If somebody breaks a 5-bit key, it will be a breakthrough,” Project 11 concluded. “That’s much smaller than BTC’s 256-bit keys, but quantum computers will get there too. When that happens, we need to know.”

Edited by Andrew Hayward