Ethereum has successfully activated its second Blob Parameter-Only (BPO) hard fork, a targeted upgrade designed to expand the network's data availability capacity to support the growing ecosystem of Layer 2 rollups. The fork, which went live on Wednesday at 1:01:11 UTC, raised the network's blob target from 10 to 14 and increased the blob limit from 15 to 21.
This technical adjustment means Ethereum can now handle up to roughly 2.6 megabytes of blob data per block, with each blob capable of carrying 128 kilobytes of data. The change is a planned, incremental step in Ethereum's scaling strategy, focusing on tuning data availability parameters rather than executing major, disruptive upgrades. Developers emphasize that the blob target (14) is the more critical figure, as it represents the sustainable level of data throughput the network aims to maintain under normal conditions to ensure node health and decentralization.
The upgrade directly benefits Layer 2 rollup networks like Base, Optimism, Arbitrum, Mantle, zkSync Era, StarkNet, and Scroll by providing more headroom for them to publish their transaction data reliably on Ethereum's base layer. According to Andrew Gross of Blockscout, "The BPO2 fork underscores that Ethereum’s scalability is now parametric, not procedural. Blob space remains far from saturation, and the network can expand throughput simply by tuning capacity."
On-chain data indicates that despite rising rollup activity, blob usage remains well below the new capacity limits. This dynamic supports Ethereum's strategy of scaling data availability incrementally before congestion emerges. Christine Erispe, a developer advocate at Ethereum Philippines, noted the fork is "impactful in cases where blobs are the bottleneck," giving rollups extra headroom and leading to "more L2 batches per unit time, or the same batches at lower marginal blob price."
The broader context includes Ethereum co-founder Vitalik Buterin's recent claim that the network has solved the blockchain trilemma of achieving security, decentralization, and scalability simultaneously, citing advances like peer data availability sampling (PeerDAS) and zero-knowledge Ethereum virtual machines (zkEVMs). Looking ahead, developers are already discussing a potential increase to the network's gas limit from 60 million to 80 million, with the larger Glamsterdam hard fork planned for 2026 expected to push scalability further by allowing gas limits as high as 200 million and introducing "perfect parallel processing."
