The quantum threat to Ethereum has become more real: Google has reduced the hacking threshold by 20 times, but protection is already on the way
March 2026 became a turning point for cryptographic security. Google Quantum AI's research team published data that fundamentally changes our understanding of the timeline for the quantum threat. According to their findings, breaking Ethereum's digital signature scheme (ECDSA) will require approximately 20 times less computational resources than previously assumed. This is not about a hypothetical threat, but a very concrete benchmark — around 1,200 logical qubits.
Previously, the industry operated with estimates of tens of thousands of qubits needed to compromise the security of each Ethereum account. Now the bar has been lowered to 1,200. Google considered this forecast realistic enough to set an internal deadline for migrating its own systems to post-quantum cryptography by 2029.
Why This Changes Everything
The vulnerability lies in the very mechanics of Ethereum transactions. When you send funds, your public key is revealed on-chain. A sufficiently powerful quantum computer can derive the private key from it and drain the wallet. Today's machines cannot do this, but 1,200 qubits is no longer science fiction — it's an engineering goal. It's important to understand: about 0.1% of all funds on the Ethereum network reside in addresses with already exposed public keys. These wallets are vulnerable today, essentially acting as "time bombs."
The threat is not limited to asset holders. Validator signatures, data availability guarantees, and zero-knowledge proof systems — on which most rollup protocols rely — are also at risk. All this infrastructure depends on mathematics that a sufficiently powerful quantum computer can break.
Ethereum Foundation Takes Action
In January 2026, the Ethereum Foundation formed a dedicated Post-Quantum Security team led by Tom Coratger. It operates fully transparently — all results are published on the project's website. One of the key researchers, Justin Drake, directly identifies protection against the quantum threat as a top strategic priority.
The Foundation also announced the Poseidon Prize — a $1 million award for breakthrough solutions in hash-based cryptography. These developments rely on three post-quantum cryptography standards approved by NIST back in August 2024.
In the near term, EIP-8141 is under consideration. This standard implements account abstraction at the network level and gives each user the right to choose their own signature scheme. It is planned to be included in the Hegota hard fork, scheduled for the second half of 2026.
Ethereum aims to complete its technical overhaul by around 2029 — the same milestone Google has set for itself. For those who want to protect themselves today, the Foundation's Kohaku project exists. It allows creating a quantum-resistant smart account based on ERC-4337 without requiring a hard fork. The cost of the procedure on the testnet is approximately $0.07.
The Rest of the Blockchain Industry Remains Silent
No major blockchain has responded to the threat like Ethereum. Bitcoin, Solana, and others face the same vulnerabilities: the ECDSA signature scheme is used everywhere. However, no project has yet assembled a dedicated post-quantum security team or presented a comparable action plan.
My analysis: The figure of 1,200 qubits is not a death sentence. Serious engineering challenges remain before a practical quantum attack can be realized. However, a 20-fold reduction in the risk estimate, especially coming from one of the world's most advanced quantum programs, is not a signal the rest of the market can continue to postpone. Ethereum demonstrates an example of a proactive approach. The rest should hurry up.