Key Insights
- In Google Quantum AI report, Cardano was ranked above Ethereum as it showed better quantum resistance.
- Exposed wallets and vulnerable smart contracts are major risks to Ethereum.
- The UTXO model used by Cardano provides increased resistance to quantum attacks in the long term.
Cardano was mentioned 5 times (plus 3 citations) on the Google Quantum AI whitepaper.
And it was ranked in the second-best tier for quantum resistance, right behind purpose-built quantum-proof chains.
Above Ethereum. Above Solana. Above XRP.
The UTXO architecture gives Cardano…
— Dan Gambardello (@dangambardello) April 1, 2026
Cardano Making Progress in Google Quantum AI Report
The recent Google Quantum AI whitepaper has rattled the crypto sector with the ranking of Cardano over Ethereum in quantum resistance. The results confused most investors and developers particularly considering the fact that Ethereum had dominated the decentralized applications and smart contracts.
The report stated that Cardano has performed better than Ethereum as well as Solana and XRP, which were ranked in the second-best rank in the field of quantum resilience. Quantum-proof blockchains were only ranked higher by specially designed blockchains.
This acknowledgement is an important achievement of Cardano, which supports the reputation of the blockchain as a research-based and security-oriented one.
The whitepaper mentions Cardano several times, indicating the increasing academic and institutional attention to its architecture. These results are now leading to a more general re-evaluation of the way blockchains need to be ready against future quantum threats.
The UTXO Model of Cardano Is Unique Because of the Following Reasons
The use of the UTXO (Unspent Transaction Output) model is one of the largest strengths of Cardano. UTXO structures provide greater transaction exposure and wallet security compared to the account-based system of Ethereum.
Public keys are not incessantly revealed in the system of Cardano following transactions. This minimizes the attack surface that quantum computers may utilize in future. Cardano offers extra protection to users because of its ability to make sensitive cryptographic data harder to see by restricting the time that the data is in view.
On the contrary, Ethereum design reveals the public keys after a transaction. These keys are stored on the blockchain permanently, which provides a long-term weakness. With the development of quantum computing, this design decision might be a significant security threat.
The results of Google give indirect support to the strategy adopted by Cardano and imply that the architecture would be more resistant to upcoming quantum threats. This competitive edge makes Cardano a good competitor in the dynamic blockchain security market.
The Structural Risks of Ethereum Get into Focus
The same report cast serious doubt on the strength of Ethereum during a quantum computing era. Five possible attack vectors were described by researchers, which focus on various elements of the network.
Wallet exposure is one of the most urgent problems. The report approximates the number of ETH already in wallets with exposed public keys to be 20.5 million. In case a quantum computer powerful enough appears, these wallets would be broken in the nearest future, which may be in a few minutes per key.
The wallets with high value are especially vulnerable. Tens of billions of dollars of digital assets could be at risk with a potential of being exposed to dozens of major wallets. More vulnerabilities are also brought about by the smart contract ecosystem of Ethereum.
Most of the smart contracts that are run by an administration, such as stablecoins and token issuance, use a set of cryptographic standards that might not resist quantum attacks. The report indicates that there are approximately 70 large contracts that are in this high risk category.
The Future of Ethereum
These risks are not being overlooked by Ethereum developers. As a reaction, a post-quantum research program was initiated earlier this year, with a long-term upgrade roadmap expected to be completed by 2029. The plan will contain various hard forks that will enhance the cryptographic defenses.
Nevertheless, these upgrades are associated with enormous challenges. The current smart contracts cannot be updated automatically through the network. Every protocol should update its codebase separately, adopt new cryptographic standards, and change keys in the cases when it is required.
This piecemeal system may slow the adoption and expose sections of the ecosystem to long durations. Other projects can postpone or even skip upgrades, which exposes the risk window.
A Movement toward Structural Resilience
The results of Google Quantum AI have changed the discussion to long-term security instead of short-term performance. Although Ethereum remains the most widely used and innovative, its architecture is under greater scrutiny now.
Cardano, in its turn, enjoys the advantage of being founded on formal approaches and proactive security standards. Its model is based on UTXO and eliminates the need for more intricate upgrades and quantum threats.






