Shor's algorithm on future quantum computers could crack ECDSA signatures, turning public keys into private keys—bad news for exposed wallets.
Fresh 2026 data shows the gap is huge:
Bitcoin's UTXO model + modern addresses (SegWit/Taproot) hide public keys until you spend. CoinShares Feb 2026 report: Only ~8% supply (~1.6M BTC) in legacy P2PK addresses has exposed keys. But critically, just 10,200 BTC sit in large enough chunks to cause real market disruption if stolen. The rest? Tiny dust scattered across 32k+ wallets—impractical to crack even with massive quantum advances. Need fault-tolerant machines ~100,000× stronger than today → threat 10+ years away.
Ethereum's account model reuses addresses; every transaction exposes the public key. Citi Institute 2026 analysis: >65% of ETH supply currently vulnerable. Higher real-time exposure makes ETH wallets riper for "harvest now, decrypt later" attacks.
BTC wins on built-in protection for dormant/ hodl funds. ETH leads on upgrade speed—Ethereum Foundation's post-quantum team is already prioritizing NIST PQC migration.
Neither faces doom tomorrow. Best moves: Stop address reuse, use hardware wallets, track PQC BIPs/EIPs.
What do you think—overhyped scare or wake-up call? Share your questions below, I'd love to chat! Thanks for reading 🙏
#Bitcoin #Ethereum #QuantumComputing #CryptoSecurity