Breaking encryption with a quantum computer just got 10 times easier

Researchers have reduced the quantum computing power needed to crack RSA encryption by a factor of ten. A study from Iceberg Quantum in Australia estimates that roughly 100,000 qubits would suffice. This lowers the previous requirement of less than one million qubits set by Craig Gidney at Google Quantum AI in 2025. Gidney had earlier cut the number from 170 million qubits in 2019 to 20 million. The new estimate builds on those algorithmic improvements but assumes qLDPC code for connecting qubits. That code allows interactions beyond nearest neighbors and increases information density. For 98,000 superconducting qubits the task would take about one month. A computation taking one day would require 471,000 qubits. The projection rests primarily on error rates and speed and applies regardless of whether the qubits are superconducting or another type. Several quantum computing companies aim to produce hundreds of thousands of qubits within the decade. Craig Gidney said the stricter demands make the hardware harder to build, which remains the greatest challenge. Scott Aaronson at the University of Texas at Austin raised concerns about the practical difficulties of engineering connections between distant qubits. IBM has promoted qLDPC codes and a spokesperson called them a cornerstone of its quantum computers. Lawrence Cohen at Iceberg Quantum warned against conservative timelines because breaking RSA would have major consequences. He noted that the method could also support improved simulations of quantum materials and chemistry.