The XRP Ledger’s quantum-security roadmap is back in focus as Ripple works to ensure migration is prepared before Q-Day—the theoretical moment when a quantum computer can break public-key cryptography used by live systems. RippleX Senior Director of Engineering Ayo Akinyele told CoinDesk that the goal is not to wait until quantum computing becomes an immediate threat, while noting that no publicly known machine has yet reached that capability.
Preparation has become more visible across major networks: Bitcoin has tested two quantum-security approaches and Ethereum has raised quantum safety in its architectural planning. A separate AI development has complicated replacement cryptography. Anthropic’s Claude Mythos Preview found an improved key-recovery attack against HAWK, a post-quantum signature candidate under consideration by NIST. For the smallest HAWK-256 configuration, expected attack work fell from roughly 2^64 operations to 2^38—about 67 million times less—after around 60 hours of model research. HAWK was not deployed on XRPL, so live accounts were not exposed, but the result showed candidate algorithms can lose ground after years of review.
XRPL currently uses elliptic-curve signatures, and signing reveals the public key. A sufficiently powerful quantum computer could theoretically calculate the corresponding private key and produce valid signatures. Although the threat is not practical today, the concern is the time required to move active accounts away from exposed classical keys. XRPL has a structural advantage: an account address and its authorized key are separate. Accounts can assign and replace a regular key through a SetRegularKey transaction without replacing the account address, preserving balances, trust lines, settings and ledger history. The limitation is that XRPL can rotate only into signature systems mainnet already recognizes; no post-quantum signer can be selected until developers implement one and validators activate it. Sui is also examining the same user problem through planned post-quantum signers that preserve existing account addresses.
Ripple’s roadmap covers two scenarios. In a planned transition, several NIST-standardized signature schemes will be compared against real XRPL workloads for public-key size, signature size and verification speed, with Project Eleven including Devnet benchmarking, validator tests and an early custody-wallet prototype. Candidate signatures are expected to run alongside existing systems before classical signatures are retired, and Ripple is targeting full post-quantum readiness by 2028. In an emergency recovery, if quantum hardware advances faster than expected, XRPL could stop accepting affected signatures, but Ripple is also exploring whether seed-derived information and post-quantum zero-knowledge proofs could provide a separate ownership test; that method remains exploratory.
Mainnet activation requires more than individual account choices. Adding new signature algorithms changes transaction rules and requires an amendment with more than 80% support from trusted validators for two weeks. Servers that lack support after activation can become amendment-blocked. Ripple has not asked XRP holders to move funds, create replacement accounts or rotate into post-quantum keys, and ordinary mainnet accounts do not yet have that option. Users should watch for a selected signature scheme, published performance benchmarks, supported wallet tools and a live amendment vote.
