Ethereum’s next major upgrade, the Fusaka hard fork, will introduce EIP-7825, setting a per-transaction gas limit cap of 2²⁴ (approximately 16.78 million gas). This change has already been activated on the Holesky and Sepolia testnets and will go live on the mainnet once Fusaka is activated.
The new cap restricts the maximum amount of gas a single transaction can consume. This is a strategic move designed to reduce the risks associated with Denial-of-Service (DoS) attacks and to enable parallel execution in future Ethereum upgrades, such as EIP-7928, also known as Glamsterdam. Previously, a single large transaction had the potential to consume an entire block's gas limit, which is approximately 45 million gas. This limitation hindered efficiency and prevented the implementation of multi-threaded execution.
With the implementation of EIP-7825, blocks will now be composed of multiple smaller, more predictable transactions. This structural change is expected to improve overall throughput and enhance network security without altering the total block gas limit.
Minimal Impact for Most Users
For the majority of Ethereum users, this update will result in no discernible changes, as most transactions already operate well below the 16 million gas threshold. However, developers who utilize batch transactions or engage in heavy deployment scripts are advised to thoroughly test their contracts. They should also consider refactoring any large operations into smaller, more manageable chunks to ensure compatibility with the new gas limits.
Developers are specifically advised to:
- •Test their transactions on the Sepolia or Holesky testnets, as these networks are already enforcing the new gas cap.
- •Re-sign any pre-built transactions that currently exceed the 16.78 million gas limit.
- •Update their tooling and gas estimation logic to accurately reflect the new per-transaction gas cap.
Step Toward Parallel Execution
The Fusaka update represents another significant milestone in Ethereum's ongoing journey toward enhanced scalability. By enforcing a per-transaction gas limit, the network is strengthening its foundational architecture for parallel processing. This development is crucial for paving the way for higher performance and more efficient block construction in future upgrades.
All major Ethereum client teams, including Geth, Erigon, Reth, Nethermind, and Besu, have already incorporated the Fusaka changes into their latest releases.