Ethereum's Sepolia testnet activates Glamsterdam, lifts gas limit near 200 million
In brief
- Sepolia activated the Glamsterdam upgrade on October 6, according to Decrypt.
- Sepolia testnet blocks now carry a gas limit of nearly 200 million.
- Sepolia blocks used roughly 24% to 43% of the limit in an October 8 snapshot.
- Mainnet stays at 60 million; no mainnet or Hoodi date has been set.
What changed on Sepolia
Gas measures computing work on Ethereum, and the gas limit caps how much of that work fits in a single block. Decrypt reported that the 200 million figure was scheduled in a commit tied to epoch 353,024, which began at 13:53:36 UTC.
The blocks aren't full, though.
An October 8 Etherscan snapshot cited by Decrypt covering 25 consecutive blocks (11,872,013 through 11,872,037) showed gas use at roughly 24% to 43% of the limit. A higher ceiling doesn't mean three times as many transactions, only that a block can hold more when demand shows up. That extra headroom is what helps keep fees from spiking when lots of users transact on Ethereum at once.
Why the limit has climbed slowly
Bigger blocks are harder on validators (the machines that stake ETH as collateral to check and confirm blocks). It's a tradeoff that has kept increases small.
Ethereum Foundation researchers had warned that limits above 40 million could "fail to propagate as expected" across the network, Decrypt reported, so the limit has risen in small steps.
According to Decrypt, a 52%-to-48% validator vote in February 2025 moved the limit from 30 million to 32 million. Decrypt reported that the limit was later raised to 60 million during 2025, and that the Fusaka upgrade, live on December 3, 2025, made 60 million the default.
Decrypt also described two other pieces of the work. Block-level access lists record which accounts and data each block touches, so transactions can be checked in parallel. Enshrined proposer-builder separation moves the block-building auction (currently run through outside middleware) into Ethereum's protocol rules.
Mainnet isn't on the calendar
The announcement set no date for the Hoodi testnet and scheduled no mainnet upgrade. Ethereum developers have described a possible gas-limit increase toward roughly 200 million after Glamsterdam, but that's a possibility they've floated, not a scheduled change. Vitalik Buterin described a longer arc in July: a plan to replace almost every major piece of the protocol over three to four years.
Sepolia has played this role before. It staged the Merge rehearsal on July 6, 2022, switching to proof of stake ahead of mainnet.
Frequently asked questions
What is the gas limit on Ethereum?
Gas is the unit that measures computing work on Ethereum. The gas limit caps how much of that work fits in a single block. A higher limit lets a block hold more when demand appears, and the extra room helps keep fees from spiking when many users transact at once.
Does Sepolia's 200 million gas limit apply to Ethereum mainnet?
No. Sepolia is a testnet whose tokens carry no real value. According to Decrypt, the announcement scheduled no mainnet upgrade and set no date for the Hoodi testnet, so mainnet keeps its 60 million gas limit. Developers have described a move toward roughly 200 million after Glamsterdam as possible, not scheduled.
Why hasn't Ethereum raised its gas limit faster?
Bigger blocks are harder on validators, which stake ETH to check and confirm blocks. According to Decrypt, Ethereum Foundation researchers had warned that limits above 40 million could fail to propagate as expected. Decrypt reported the limit has gone up in small steps, from 30 million to 32 million in February 2025 and then to 60 million during 2025.
