Ethereum's Sepolia test network activated Glamsterdam on October 6 with a block gas limit near 200 million, over three times mainnet's 60 million.
Ethereum's Sepolia test network activated the Glamsterdam upgrade on October 6 and began producing blocks with a gas limit of nearly 200 million, more than three times the 60 million that Ethereum's main network allows. Gas is the unit that measures computing work on Ethereum, and the gas limit caps how much of that work fits into a single block.
The 200 million figure was scheduled in a commit tied to epoch 353,024, a 6.4-minute time marker in Ethereum's calendar that began at 13:53:36 UTC.
Blocks used only a fraction of that room. A snapshot of 25 consecutive blocks on Etherscan taken on October 8, numbers 11,872,013 through 11,872,037, shows gas use at roughly 24% to 43% of the limit.
A higher ceiling does not mean three times as many transactions, only that a block can hold more when demand shows up. For everyday users, that headroom is what helps keep fees from spiking when many people use Ethereum at once, because congestion feels like strangers outbidding each other to get into the next block.
Bigger blocks are harder on validators, the computers that put up ETH as collateral to check and confirm each block. Ethereum Foundation researchers had warned that limits above 40 million could "fail to propagate as expected" across the network, so the number has crept up in small steps.
One of those steps was a 52%-to-48% validator vote in February 2025 that moved the limit from 30 million to 32 million. The limit was later raised to 60 million during 2025, double the original 30 million, and the Fusaka upgrade , which went live on December 3, 2025, made that the default.