Quantum Computers Unlikely to Threaten Bitcoin in the Near Term, Experts Say

Quantum computers are unlikely to pose a threat to Bitcoin anytime soon, according to developer and crypto custody company Casas co-founder Jameson Lopp. The remarks come as debate intensifies over whether progress in quantum computing is approaching a level that could endanger the cryptographic systems securing blockchains such as Bitcoin and Ethereum. Experts Split On When Quantum Computers Could Threaten Bitcoin In a recent X (formerly Twitter) post, Lopp said that quantum computers will not break Bitcoin soon. No, quantum computers wont break Bitcoin in the near future. Well keep observing their evolution..We should hope for the best, but prepare for the worst, Lopp posted. Lopps timeline outlook aligns with many experts, who assert that quantum computers pose no immediate threat to the network. Adam Back, CEO of Blockstream, recently commented that the short-term risks are nil. This whole thing is decades away, its ridiculously early and they have massive RD issues in every vector of the required applied physics research to even find out if its possible at useful scale. but its ok to be quantum ready and, Back said. Charles Hoskinson, founder of Cardano, took a similar stance. He argued that current quantum threats to blockchain are overstated and not urgent at present. Hoskinson also noted that while blockchains could transition to quantum-resistant cryptography, doing so would come with significant efficiency costs. However, other experts believe the timeline is tightening.David Carvalho, CEO of Naoris Protocol, has warned that quantum computers could compromise Bitcoins security within the next 2 to 3 years. Separately, Michele Mosca, a researcher at the University of Waterloo, forecasted a 1-in-7 probability that fundamental public-key cryptography could be broken as early as 2026. On Metaculus, the timeline for quantum computers ability to factor one of the RSA numbers has also shortened. It has moved down from 2052 to 2034. The Quantum Doomsday Clock project is even more urgent. It projects that quantum computers will crack Bitcoins encryption by March 8, 2028. Why Quantum-Proofing Bitcoin Is Hard While experts disagree on the timeline, many agree on one point. If quantum-resistant upgrades ever become necessary, implementing them would take time. Lopp mentioned that migration to post-quantum standards could take 5 to 10 years. When asked why discussions around quantum computing risks tend to focus on Bitcoin rather than traditional financial institutions like banks, Lopp pointed to a fundamental difference in how quickly systems can be upgraded. Because they can upgrade their systems orders of magnitude faster than the Bitcoin ecosystem, he said. Meanwhile, another market watcher detailed why transitioning blockchain networks to quantum-resistant cryptography is significantly more complex than in centralized systems. For the banking sector and the internet, the migration is comparatively straightforward. When cryptographic standards change, they can roll out new algorithms through coordinated updates, revoke old keys, reissue credentials, and even forcibly migrate users, he stated. Bitcoin, by contrast, lacks a central authority capable of mandating such changes. Any shift to post-quantum signatures would require broad social consensus, extensive technical coordination, and voluntary user participation. The analyst noted that lost, abandoned, or inactive Bitcoins and wallets cannot be migrated. As a result, part of the supply will remain permanently vulnerable once quantum attacks become viable. Technical constraints further complicate the process. Most post-quantum signature schemes have much larger key sizes and signatures than ECDSA. In a system already constrained by block size limits and global replication, this is not a trivial change. What is a manageable overhead for a bank server or a web connection becomes a consensus-level scalability concern in a blockchain, the post read. Thus, the same decentralization that underpins Bitcoins security and resilience also makes cryptographic adaptation slower, more complex, and harder to execute than in centralized systems.