Vitalik Calls Ethereum (ETH) ZK Speed Race Won After 99% of Proofs Land in Under 10 Seconds

Security Now Outranks Speed

Ethereum (ETH) co-founder Vitalik Buterin said on Thursday, October 15 that the race to make zero-knowledge proofs fast enough for the network has been won, and that security should now absorb the full attention of zkEVM builders. He published the remarks on X within hours of ZKsync announcing it had achieved real-time proving on a single consumer graphics card, congratulating the ZKsync airbender team first and adding that the battle for speed is, in his words, “definitively won.” The declaration lands while the Ethereum roadmap leans further into cryptographic verification, and while the Ethereum (ETH) price slipped 5.7% over the past 24 hours, a reminder that engineering milestones rarely move markets on their own. zkEVMs, the systems that prove Ethereum's execution, now face three tests in his framing: they must match the Ethereum specification, keep the cost of running a prover within each block's gas fee budget, and rest on a sound proof system. He wants each of the three formally verified, meaning proven mathematically rather than only exercised through testing. Speed carried structural weight: under proof of stake, validators re-run every transaction to check each block that Ethereum (ETH) adds every 12 seconds. A zero-knowledge proof, which confirms a computation ran correctly without repeating it, would let them verify a short cryptographic proof instead, cutting the per-block effort to a fraction. Cutting that workload has been one of the long-promised payoffs of the zero-knowledge research line, and the reason competing proving teams have spent years publishing benchmarks.

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ZKsync's 7,200-Block Benchmark

The numbers behind the claim come from ZKsync's own evaluation of its new Airbender Prime prover: across 7,200 consecutive mainnet blocks, the system produced 99% of proofs in under 10 seconds. No block in that sample needed the full 12-second window, and the figures, while striking, are self-reported rather than independently audited. Real-time proving has long been treated as the threshold where a zkEVM stops being an opt-in scaling experiment and starts functioning as infrastructure, because only then can proofs keep pace with the chain they summarize. For an outside check, ZKsync points to ETHproofs, a public prover leaderboard where Airbender Prime ranks first on average proving time; the board also tracks cost, giving institutions a benchmark beyond vendor claims. Hardware is the second half of the story. Proving on one graphics card instead of a cluster of specialized machines lowers the entry cost enough, in the company's argument, for more institutions and independent operators to join the proving set. That decentralization argument carries weight across the layer 2 systems built on zkEVM technology, where reliance on a small pool of professional provers is a standing criticism. Airbender Prime remains a ZKsync product rather than an Ethereum (ETH) protocol change. It leaves ETH supply, fee mechanics and staking rewards untouched, so nothing about issuance or on-chain economics moves with this milestone. The bigger commercial stake sits elsewhere: ZKsync pitches the prover to banks on the argument that even a hacked server could not get a rule-breaking ledger update verified. That promise only holds if the fast prover itself is free of defects, which turns audits and formal checks into the deciding factor for which zkEVMs institutions can trust.

What Formal Verification Decides

Our read is that the market treated the announcement as roadmap sentiment rather than a protocol event. Airbender Prime changes no fee, issuance or validator economics today, so the 5.7% slide tracks macro conditions and fund flows more than the proving claim; the coin had already slipped below $2,400 in early Thursday trade. Structure is shifting underneath, though: MetaMask staking exits pushed the validator count down 7.7% in a month, which makes any workload cut for validators operationally relevant. The near-term test is the one Buterin set himself: formal verification and audits will decide which zkEVMs Ethereum can trust, and readers tracking levels can follow our Ethereum technical analysis.