Recent advances in quantum computing are steadily reducing the cost of breaking modern public-key cryptography. In our report, The Quantum Threat to Blockchains – 2026, we analyze the trajectory toward “Q-Day,” the moment a cryptographically relevant quantum computer can break existing public-key cryptography. The model's baseline places Q-Day in 2033, with optimistic and pessimistic scenarios at 2030 and 2042.
Blockchain systems are particularly exposed: addresses hold meaningful value under the same public key for years; signature schemes are baked into consensus rules and transaction formats that are hard to change across an entire ecosystem; and once a key is compromised there is no recovery mechanism. The report highlights risks, timelines, and what each of the major blockchains will have to change to remain secure.
Read the full report here: The Quantum Threat to Blockchains – 2026 (PDF)