Ethereum’s Glamsterdam upgrade is scheduled for Hoodi, a test network, on Oct. 26, 2026, at 17:42:48 UTC, giving its node operators a deadline to upgrade software. The test pairs changes to block production and validation with a scheduled 200 million gas target.
The Ethereum Foundation’s Oct. 16 announcement fixes the next testnet deployment after Glamsterdam’s Oct. 6 activation on Sepolia. Mainnet timing remains undecided. ETH holders and mainnet operators have no action to take as a result of this Hoodi announcement.
All Hoodi operators must update their execution and consensus clients before activation. Validators must update both the beacon node and validator client, and review new duties, builder-tooling compatibility and gas-limit settings to follow the upgraded testnet.
The Foundation’s confirmed Hoodi releases, as checked Oct. 17, are:
| Layer | Client | Listed release |
|---|---|---|
| Execution | Besu | 26.10.0 |
| Execution | Ethrex | 30.0.0-rc.2 |
| Execution | Nethermind | 2.2.0 |
| Consensus | Lodestar | 1.50.0 |
| Consensus | Nimbus | 26.10.1 |
| Consensus | Prysm | v7.3.0 |
| Consensus | Teku | 26.10.1 |
Ethrex’s listed version is a release candidate. Grandine, Lighthouse, Erigon, go-ethereum and Reth remain unlisted; operators should use releases whose notes confirm this Hoodi activation.
Besu 26.10.0 migrates Bonsai code storage on first startup and retains more history when pruning. Downgrading requires the documented besu storage revert-code-format command before an older version can reopen the database.
What the scaling test changes
Hoodi’s 200 million gas target is a planned budget for computational work per block. The gas-limit schedule sets client defaults and recommendations while preserving operator preferences. The actual block limit adjusts gradually under existing rules, so the target is not an instantly enforced ceiling.
Throughput depends on transaction complexity, while fees also depend on demand.
Glamsterdam combines Amsterdam on the execution layer with Gloas on the consensus layer. Enshrined proposer-builder separation moves the exchange between block proposers and builders into the protocol and gives validators more time to check execution. Block-level access lists record accessed accounts, storage and state changes so clients can perform more work in parallel.
Developers also have testing to do: changed gas pricing can affect contracts that rely on fixed stipends, hardcoded limits or remaining-gas assumptions. The Foundation advises testing contracts and gas estimation under the new rules.
