Ethereum’s Sepolia testnet activated the Glamsterdam upgrade on Oct. 6 and began producing blocks with a gas limit of nearly 200 million, more than three times the 60 million currently allowed on Ethereum’s main network.
On Ethereum, gas measures computational work, and the gas limit sets how much of that work can fit into a single block.
The change was scheduled at epoch 353,024
The nearly 200 million figure was scheduled in a commit tied to epoch 353,024, a 6.4-minute marker in Ethereum’s calendar that began at 13:53:36 UTC.
A higher ceiling does not mean blocks will suddenly carry three times as many transactions. It means a block can hold more when demand arrives.
For regular users, that extra room can help keep fees from jumping when many people use Ethereum at the same time. The report describes congestion as users effectively outbidding one another for space in the next block.
Recent blocks used only part of the available room
A snapshot of 25 consecutive blocks on Etherscan taken on Oct. 8, covering block numbers 11,872,013 through 11,872,037, showed gas use at roughly 24% to 43% of the limit. In other words, Sepolia’s block capacity has been raised sharply, but actual usage in that sample remained far below the cap.
Larger blocks also increase validator load
Bigger blocks are harder on validators, the computers that stake ETH as collateral to check and confirm each block. Ethereum Foundation researchers had previously warned that limits above 40 million could "fail to propagate as expected" across the network, which is why the parameter has been raised in smaller steps over time rather than in one jump.
One of those steps came in February 2025, when validators voted 52% to 48% to move the limit from 30 million to 32 million. The limit was later raised to 60 million during 2025, doubling the original 30 million. The Fusaka upgrade, which went live on Dec. 3, 2025, made that figure the default.
Two roadmap changes are aimed at handling more load
The report points to two changes on Ethereum’s roadmap that are meant to help the network carry more demand.
- Block-level access lists would record which accounts and data each block touches, allowing computers to check many transactions at once instead of one by one.
- Enshrined proposer-builder separation would move the auction that decides who assembles each block into Ethereum’s own rules. Today, that process runs through outside middleware.
Ethereum co-founder Vitalik Buterin outlined the longer-term direction in July, when he described a plan to replace almost every major part of the protocol over three to four years. Against that backdrop, Glamsterdam is the nearer-term step. Ethereum developers have also described a possible gas-limit increase toward roughly 200 million after it.
Sepolia remains a test network, and no mainnet date has been set
Sepolia is a testnet, a practice network where the tokens carry no real value, allowing developers to test changes and break things without costing anyone money. It also served as a rehearsal ground for the Merge on July 6, 2022, when it switched to proof of stake ahead of mainnet.
The announcement sets no date for Hoodi, another public testnet, and does not schedule a mainnet upgrade. For now, Ethereum mainnet remains at a 60 million gas limit.