Bitcoin has fallen roughly 46% from its October 2025 all-time high of $126,100 to around $67,000 in early 2026. Etherium has declined even more sharply, dropping approximately 58% to near $1,950. Amid this volatility, some commentators have revived an old concern: quantum computing.
However, leading developers and researchers argue that quantum fears are not driving the current downturn. Instead, macroeconomic pressures, capital rotation into AI sectors, and liquidity dynamics appear far more relevant. While quantum computing poses a theoretical risk to cryptographic systems, current evidence suggests it remains a long-term challenge, likely a decade or more away, rather than an imminent existential threat.
The core concern stems from Shor’s algorithm, which could theoretically allow a sufficiently powerful quantum computer to derive private keys from public keys. If that became feasible, wallets with exposed public keys,particularly older addresses or reused keys,could be compromised.
Estimates suggest that 20% to 50% of Bitcoin’s circulating supply could theoretically be exposed if quantum attacks became viable. However, this scenario assumes the existence of fault-tolerant quantum machines with approximately 1.9 billion stable logical qubits. Today’s most advanced systems operate with only hundreds to a few thousand noisy qubits, orders of magnitude below what would be required.
Experts emphasize that scalable, error-corrected quantum computers would need to be 10,000 to 100,000 times more powerful than current hardware to pose a real threat to Bitcoin’s elliptic curve cryptography (ECDSA).
Bitcoin developer Matt Carallo recently dismissed speculation that quantum computing is responsible for recent price declines, noting that if quantum were the primary driver, Ether’s relative performance might look different given Ethereum’s more proactive upgrade roadmap.
Carallo characterized quantum as a “long-term risk” that market participants do not currently view as imminent. He attributed recent volatility more to capital flows into artificial intelligence sectors than to cryptographic concerns.
Even cautious voices frame the risk in future terms. Ethereum co-founder Vitalik Buterin has estimated roughly a 20% chance of significant quantum breakthroughs before 2030. While nontrivial, that probability still implies uncertainty rather than inevitability.
Quantum computing researcher Scott Aaronson has described the threat as a “live possibility” within the 2028-2030 timeframe, but acknowledges major engineering hurdles remain. Meanwhile, investor Kevin O’Leary has argued that targeting Bitcoin would not be the most efficient or economically rational use of quantum resources compared to fields like medical research or materials science.
Recent advancements in quantum computing, including IonQ roadmap updates and progress toward NIST-standardized post-quantum cryptography demonstrate forward momentum. Yet fundamental barriers persist:
These constraints suggest that practical quantum attacks against Bitcoin or Ethereum remain at least 10-15 years away under most projections.
The crypto industry is not standing still. Ethereum’s 2026 roadmap includes exploration of post-quantum cryptographic standards within major upgrades. Bitcoin developers have discussed potential hard forks introducing quantum-resistant signature schemes such as Dilithium or XMSS.
Importantly, only coins with revealed public keys are vulnerable in early attack scenarios. Estimates suggest between 4 and 10 million BTC might fall into this category. Users can proactively migrate funds to quantum-resistant addresses once standards are implemented.
In other words, the industry retains significant flexibility to transition before any large-scale threat materializes.
Some institutions have issued precautionary warnings. Asset managers have included quantum risk disclosures in ETF filings, and certain portfolio strategists advocate monitoring cryptographic vulnerabilities.
However, these statements reflect risk management practices rather than predictions of imminent collapse. To date, no credible evidence suggests a breakthrough capable of threatening current blockchain security.
Market dynamics in 2026 appear far more influenced by liquidity conditions, regulatory developments, and competition for capital with AI and emerging technologies than by quantum computing fears.
The quantum era will eventually arrive, but not tomorrow. Current technological limitations, combined with active development of post-quantum cryptography, position Bitcoin and Ethereum to adapt well before existential risks emerge.
Rather than fueling panic, quantum research should motivate proactive upgrades and resilience planning. As history has shown, the crypto ecosystem evolves rapidly in response to emerging threats.
For investors and developers alike, the more immediate focus remains adoption, scalability, and macroeconomic conditions. Quantum computing represents a future engineering challenge, not a present market driver.
