Quantum 'Q-Day' Threat Could Undermine Global Encryption by 2029

Quantum computers are expected to reach the capability to break widely used public‑key encryption by around 2029, a moment dubbed “Q‑Day”. Experts warn this could expose banking accounts, emails, medical records, biometric data and cryptocurrency wallets.

Tech firms such as Google, IBM and Cloudflare are already developing post‑quantum cryptographic standards, while governments and international standards bodies work on migration plans. Researchers also caution about a “Harvest‑Now‑Decrypt‑Later” strategy, where adversaries collect encrypted data today to decrypt it once quantum machines become powerful enough.