Ripple has announced a detailed four-phase plan to make the XRP Ledger resistant to quantum computing threats by 2028, positioning the network among the first major blockchains to formally commit to a post-quantum security timeline.
The initiative follows a March 2026 finding by Google's Quantum AI team indicating that 500,000 physical qubits could be sufficient to break elliptic curve cryptography—the mathematical foundation protecting private keys across most blockchains. At that threshold, a quantum computer could derive a private key from an exposed public key in approximately nine minutes.
The Four-Phase Roadmap
Phase 1 establishes emergency contingency measures. If quantum threats materialize before the full upgrade completes, this phase would trigger rapid migration of accounts to quantum-safe alternatives.
Phase 2 is currently underway during the first half of 2026. Ripple is testing NIST-standard post-quantum algorithms, specifically ML-DSA and Dilithium, in collaboration with Project Eleven. The partnership focuses on benchmarking performance, running tests, and developing custody prototypes to ensure quantum resistance does not degrade network speed or user experience.
Later phases aim to introduce a formal XRPL amendment for native post-quantum support and achieve full quantum readiness by 2028. Testnet deployments are expected throughout mid-2026.
Current XRP Exposure
An independent audit found that only 0.03% of XRP's total supply sits in dormant accounts with exposed public keys—the specific vulnerability quantum computers would exploit. Active accounts that have not broadcast transactions do not reveal their public keys on-chain.
By comparison, Bitcoin faces considerably larger exposure through older pay-to-public-key addresses with fully visible public keys on the blockchain.
The Broader Context
The concept of "harvest now, decrypt later" describes adversaries collecting encrypted data and signed transactions today for retroactive decryption once quantum computers become sufficiently powerful.
Google's March 2026 research substantially compressed previous timelines. Earlier estimates suggested millions of qubits would be required to break elliptic curve cryptography. Quantum hardware capabilities have roughly doubled every few years, according to available data.
ML-DSA, formerly known as CRYSTALS-Dilithium, is among the cryptographic algorithms NIST standardized specifically to resist attacks from both classical and quantum computers. Dilithium signatures are approximately 40 times larger than current ECDSA signatures, potentially affecting transaction throughput, storage requirements, and network bandwidth.
