Ripple prepares XRP Ledger for quantum computing risks ahead of Q-Day

Ripple has laid out a detailed four-phase plan to make the XRP Ledger quantum-proof by 2028, responding to research suggesting that the cryptographic foundations underpinning most blockchains could be cracked faster than previously assumed. The roadmap, announced on April 20, 2026, puts XRPL among the first major blockchain networks to formally commit to a timeline for post-quantum security. The urgency stems from a March 2026 finding by Google’s Quantum AI team: just 500,000 physical qubits could be enough to break elliptic curve cryptography, the math that keeps private keys private across virtually every blockchain in existence. At that threshold, a sufficiently powerful quantum computer could derive a private key from an exposed public key in roughly nine minutes. The four-phase playbook Ripple’s roadmap starts with what it calls “Phase 1: Q-Day readiness,” essentially an emergency contingency plan. If credible quantum threats materialize before the full upgrade is complete, this phase would trigger a rapid migration of accounts to quantum-safe alternatives. Phase 2 is already underway during the first half of 2026. Ripple is testing NIST-standard post-quantum algorithms, speci...