Ethereum is testing how much cheaper block space it can safely create

Ethereum has prepared to test a 200 million gas limit on Sepolia under the Glamsterdam upgrade, putting more than three times the network's previous block capacity through a public test before developers decide what could eventually work on mainnet.

Summary

• Ethereum is testing a 200 million gas limit on Sepolia, up from roughly 60 million, as Glamsterdam puts substantially larger blocks through a public network test.
• Prysm released version 7.2.1 shortly before activation so validators automatically use the new limit instead of remaining at 60 million unless operators change the setting manually.
• More block capacity can give transactions additional room during periods of heavy demand, though a 200 million gas limit does not automatically mean lower fees for users.
• Sepolia will help developers assess whether validators can reliably handle the added workload before Glamsterdam reaches Ethereum mainnet, where no activation date has been set.

According to Prysm's Oct. 5 release notes, validator client version 7.2.1 has added Sepolia's new gas limit schedule so validators automatically propose blocks using the 200 million setting once Glamsterdam activates. The upgrade is scheduled for Oct. 6 at 13:53:36 UTC.

Prysm 7.2.0 supported the Sepolia fork but was released before the 200 million setting was added to Sepolia's configuration. Validators using that version would default to 60 million gas after activation unless operators manually changed their proposer settings.

Version 7.2.1 removes that extra step by adding the schedule directly to the client. Operators can still choose another limit through proposer settings, the keymanager API or Prysm's suggested gas limit option.

The timing matters for what developers are trying to measure on Sepolia. A mix of validators proposing blocks at 60 million and 200 million gas would give the network less consistent exposure to the larger blocks that Glamsterdam is designed to test.

Ethereum is testing how much block space validators can handle

Sepolia's move from roughly 60 million to 200 million gas gives Ethereum developers a public environment to see how validators cope when substantially more computation can fit inside each block.

A block gas limit determines the maximum amount of gas that transactions inside a block can consume. Raising the limit does not directly set the fee paid by an individual user, but it creates more room for transactions when demand for block space rises.

Ethereum's mainnet raised its gas limit to 60 million in November 2025 after more than 513,000 validators signaled support for the change. The adjustment gave blocks more capacity to process transactions while Ethereum continued preparing protocol changes intended to support higher throughput.

Glamsterdam takes that work much further. The Ethereum Foundation describes the upgrade as part of its Layer 1 scaling roadmap, with enshrined proposer builder separation and Block Level Access Lists changing how blocks are produced and validated.

A higher gas ceiling can create room for more swaps, stablecoin transfers, smart contract interactions and other transactions within the same block. When demand is high, having more available block space can reduce the amount of competition among users trying to get transactions included.

It does not mean a 200 million gas limit would automatically make Ethereum transactions cheap. Fees still depend on network demand and the type of activity being performed, while Glamsterdam separately changes how certain operations are priced.

Glamsterdam changes what Ethereum charges for

More block capacity creates another problem for Ethereum because not every operation puts the same burden on the network.

Some actions require computation that ends when a transaction finishes. Others create data that Ethereum nodes may have to keep as part of the network's state.

Glamsterdam addresses that difference through changes including EIP 8037, which changes the cost of creating state. The Ethereum Foundation says state creation has historically been cheap relative to the permanent storage burden it places on nodes.

The proposal ties charges more closely to the amount of permanent data an operation creates or accesses. As crypto.news previously reported, Ethereum Foundation developer Parithosh Jayanthi said during earlier Glamsterdam testing that high level computation would become cheaper while state would become more expensive.

Developers have already warned that the repricing can affect some applications. Contracts that rely on fixed gas assumptions, 2,300 gas stipends or specific gas limits may need changes before Glamsterdam reaches mainnet, while most contracts tested through transaction replays were unaffected. The gas compatibility warning covered EIP 8037 and EIP 8038, which changes the cost of accessing accounts and storage.

The combination lets Ethereum experiment with more execution capacity while putting tighter economic limits on operations that could make its permanent state grow too quickly.

The 200 million gas test has already cleared a private rehearsal

Sepolia will not be the first time Glamsterdam has operated around the 200 million level.

Glamsterdam Devnet 11 previously moved from 60 million to 200 million gas during a controlled rehearsal in September. The network used 84,000 validators across several clients and carried the core EIPs planned for the public test.

The Devnet 11 capacity test followed problems during earlier Glamsterdam development networks. Devnet 8 encountered non finality around its Gloas activation, while other testing exposed issues affecting execution clients before developers moved through further iterations.

Sepolia puts the upgrade into a public testnet environment where operators run different clients and configurations. Ethereum developers can use the test to see whether the higher capacity remains stable under conditions closer to a live network.

Prysm's last minute update is part of that preparation. Version 7.2.1 includes the Sepolia gas schedule at epoch 353,024 and makes 200 million the default for validators after the Gloas fork.

Mainnet will not move to 200 million on Oct. 6

The Sepolia test does not raise Ethereum mainnet's gas limit to 200 million.

Ethereum's official Glamsterdam schedule lists only Sepolia for Oct. 6. Hoodi and mainnet activation dates remain undecided, and the Ethereum Foundation said separate announcements will be made after client teams agree on those deployments.

Sepolia operators need compatible execution and consensus clients to follow the upgraded network. Prysm is one of several consensus clients involved, alongside Lighthouse, Nimbus, Teku, Lodestar and Grandine.

Ethereum developers had already identified the 200 million level as an important part of Glamsterdam testing. The network's roadmap says state growth could become unsustainable as Ethereum scales toward the capacity enabled by the upgrade without corresponding changes to gas pricing.

Work beyond Glamsterdam is examining the same constraint. Proposals being considered for Hegotá include changes intended to account for transaction data and state creation as block limits move higher, with developers reviewing further gas changes as part of Ethereum's 2027 upgrade planning.

For Sepolia, the immediate test starts at epoch 353,024. Validators running Prysm 7.2.1 will default to the 200 million gas setting when Glamsterdam activates, while Hoodi and Ethereum mainnet still have no confirmed Glamsterdam activation dates.