Quantum Computer Could Break Bitcoin Encryption in Just 26 Days

Researchers at IonQ have published a study estimating that a quantum computer with 20,000 physical qubits could break Bitcoin's secp256k1 elliptic curve encryption in approximately 26 days. This is according to a research paper titled 'Computing 256-bit elliptic curve discrete logarithms in 26 days on a fault-tolerant trapped-ion quantum computer with 20,000 qubits.'

The study uses IonQ's Walking Cat architecture, which was published in April 2026, and estimates that the computation would require 19,397 physical qubits, 1,457 logical qubits, and 39 million Toffoli gates at the logical level. The result aligns with systems on IonQ's hardware roadmap targeting the 2028 timeframe.

IonQ President of Quantum Computing Chris Ballance stated that this is the first time a utility-scale quantum algorithm has been estimated without approximating away parts that dominate a real machine's runtime. The company emphasized that the cryptographic exposure relates to authentication and integrity rather than confidentiality, and that standardized mitigation methods are available.