EIP-4844, known as proto-danksharding, is the Ethereum upgrade that slashed layer 2 transaction fees by introducing a new way to handle rollup data. Activated in March 2024 as part of the Dencun upgrade, EIP-4844 made using Arbitrum, Optimism, Base, and other L2s dramatically cheaper. In this guide, we explain what EIP-4844 changed and why it matters.
What Is EIP-4844?
EIP-4844 (Ethereum Improvement Proposal 4844) introduced “blob-carrying transactions” — a new transaction type that lets layer 2 rollups post large amounts of data to Ethereum cheaply. Before EIP-4844, rollups published their data as regular calldata, competing for the same expensive block space as everyone else. Blobs created a separate, cheaper lane dedicated to rollup data.
The name “proto-danksharding” signals that this is a stepping stone toward full danksharding — Ethereum’s long-term scaling plan — delivering most of the fee benefits long before full sharding arrives.
The Problem EIP-4844 Solved
Rollups work by executing transactions off-chain and posting compressed data back to Ethereum mainnet for security. That data posting was the dominant cost of running a rollup — and therefore the dominant cost passed to users. As L2 adoption grew, data costs grew with it, threatening the entire scaling roadmap. EIP-4844 attacked this bottleneck directly by making data availability roughly an order of magnitude cheaper.
How Do Blobs Work?
- Separate fee market: Blobs have their own pricing, independent of regular gas. When blob demand is low, blob fees are minimal — even near zero.
- Temporary storage: Unlike calldata, which lives on-chain forever, blobs are only stored by consensus nodes for about 18 days — long enough for verification and fraud proofs, without permanent bloat.
- Large capacity: Each block can carry multiple blobs (targeting 3, max 6), each holding about 128 KB of data.
- Forward compatible: The design anticipates full danksharding, when blob capacity will expand enormously.
The result: rollups’ data costs collapsed, and L2 transaction fees fell from dollars or tens of cents to fractions of a cent on many networks.
EIP-4844’s Impact on Layer 2 Fees
The fee reductions after Dencun were dramatic and immediate. Median transaction costs on major rollups dropped by 90 percent or more in many cases. This transformed the user experience: activities that were uneconomical on L2s — micropayments, gaming transactions, frequent DeFi interactions — suddenly became viable. EIP-4844 effectively completed the economic case for moving everyday activity off mainnet.
What EIP-4844 Did Not Do
It is important to be clear about the limits:
- Mainnet fees unchanged: EIP-4844 targeted rollup data costs, not regular Ethereum transactions. L1 gas fees work exactly as before.
- Not full sharding: Blob capacity is limited; if L2 demand grows enormously, blob fees will rise too — that is what full danksharding will eventually address.
- Data is temporary: Applications needing permanent on-chain data must arrange their own long-term storage.
Proto-Danksharding and the Road to Full Danksharding
Full danksharding will massively expand blob capacity — from a handful per block to potentially dozens — along with innovations like data availability sampling that let nodes verify blob data without downloading all of it. EIP-4844 was deliberately designed as the first step: it shipped the transaction format, fee market, and cryptography that full danksharding will build on. Ethereum’s scaling roadmap is now a matter of expanding what proto-danksharding started.
What This Means for Users and Developers
- Users: Default to reputable layer 2s for everyday transactions; keep mainnet for high-value settlement and long-term holdings.
- Developers: Design with blobs in mind — data-heavy applications are now economically feasible on L2s.
- Ecosystem: Cheaper L2s accelerate the migration of activity off mainnet, which is exactly what Ethereum’s rollup-centric roadmap intends.
How the Blob Fee Market Works
Blobs introduced Ethereum’s first truly independent fee market. Each block targets 3 blobs, with a maximum of 6, and a dedicated blob base fee adjusts based on demand — rising when blocks are full of blobs, falling when they are empty. Because this market is separate from regular gas, a frenzy of NFT minting on mainnet does not raise blob prices, and heavy rollup usage does not raise regular gas prices. The two lanes operate independently.
In practice, blob fees have often been extremely low, sometimes near zero during quiet periods — a testament to how much headroom EIP-4844 created. But the mechanism is designed to find equilibrium: if dozens of rollups compete for limited blob space, prices rise and the cheapest data gets priced out, exactly as intended. This dynamic is a preview of full danksharding economics, where vastly expanded blob capacity will keep data cheap even under heavy adoption. For now, EIP-4844’s fee market is working precisely as its designers hoped.
The Bottom Line
EIP-4844 was one of Ethereum’s most impactful upgrades: a relatively contained technical change that made layer 2 fees collapse and validated the rollup-centric scaling strategy. Proto-danksharding proved the concept; full danksharding will scale it. For users, the takeaway is simple — Ethereum’s future is multi-layered, and thanks to EIP-4844, the layers where daily life happens are now remarkably cheap.
