Ethereum successfully activated its Fusaka upgrade on Wednesday at 21:49:11 UTC at epoch 411392, implementing several significant protocol improvements aimed at enhancing scalability and layer-2 network performance.
The Fusaka upgrade is today.
— Ethereum (@ethereum) December 3, 2025
Ethereum is securely scaling. pic.twitter.com/YaJ5WL4tSc
The name is a portmanteau of Fulu and Osaka, representing the simultaneous upgrades to Ethereum's consensus and execution layers, respectively.
The upgrade, which comes after May 2025's Pectra , increases the gas limit to 60 million per block and enables quadrupled blob capacity through PeerDAS (Peer Data Availability Sampling), a mechanism that reduces the data verification burden on nodes. According to the network's development team, Fusaka also delivers a 530 GB reduction in node synchronization overhead and introduces 32-slot proposer lookahead functionality.
PeerDAS represents a fundamental shift in how Ethereum handles data availability. Rather than requiring every node to download complete blob files for verification, the system now allows nodes to validate data by checking small, random samples. This change is expected to significantly reduce bandwidth requirements and operational costs for rollup networks like Base, Arbitrum, Optimism, and zkSync, which rely on Ethereum for settlement.
The upgrade's expanded blob capacity could enable up to eight times greater data throughput for layer-2 rollups, addressing a key bottleneck as these networks have grown rapidly over the past year.
Bitwise analyst Max Shannon characterized Fusaka as the type of infrastructure improvement that markets often underappreciate initially but later recognize as foundational. The firm highlighted the upgrade's introduction of a minimum blob base fee through EIP-7918, which establishes a floor for blob pricing tied to execution fees, or approximately one-sixteenth of the execution base fee.
Today is a big day in Ethereum's history.
— Max Shannon (@cornMaxy) December 3, 2025
It marks a major shift in Ethereum’s core development culture.
It is the first time in history, two scaling-focused upgrades have been released in one year.
Although Ethereum upgrades have been shown to have little impact on price,… pic.twitter.com/KCEuesLGVA
This fee structure addresses an economic concern that emerged after last year's Dencun upgrade, when blob fees occasionally dropped near zero during low-activity periods, reducing ETH burn rates and weakening the connection between network usage and value accrual.
With the gas limit increase, Ethereum's transaction capacity is expected to roughly double over the coming year, potentially easing fee pressure during periods of high demand. The combination of greater capacity and improved data handling is designed to make the network more scalable without increasing hardware requirements for node operators.
The Ethereum Foundation said its community members will continue monitoring network performance in the 24 hours following activation to identify any potential issues.
