Ethereum’s “Dencun” hard fork upgrade is a major milestone in the network’s scaling roadmap. Introducing Proto-Danksharding, it targets Ethereum’s high gas fees. We explain the mechanics and impact of this upgrade.
The Core Feature: EIP-4844
Dencun’s central improvement is EIP-4844 (Proto-Danksharding).
- The “Blob” Data Space: Previously, Layer 2 networks posted data into Ethereum’s expensive call data storage. EIP-4844 creates temporary data packages called “Blobs” that expire after a few weeks, drastically reducing mainnet data verification costs.
Layer 2 Fees Plummet 90%+
With Blobs active, transaction costs on L2 networks (like Arbitrum, Optimism, and Base) plummeted by over 90%. Users can interact with smart contracts for fractions of a cent, eliminating a major user-experience barrier for dApps.

