Ethereum blobs benefit from a guarantee of about 18 days, but they do not necessarily disappear afterwards. Since Dencun, March 13, 2024, layer 2 networks publish their data there at lower co
Ethereum blobs benefit from a guarantee of about 18 days, but they do not necessarily disappear afterwards. Since Dencun, March 13, 2024, layer 2 networks publish their data there at lower cost. On October 27, 2026, the Blobscan archive still indicated three storage locations for the first blob it recorded, published on March 13, 2024.
Layer 2 networks, like Base or Arbitrum, group thousands of operations. They then publish on Ethereum the data that allows verifying them. Before March 2024, this data most often went through the “calldata” of transactions. This field remains stored forever in the chain’s history.
The EIP-4844, activated by Dencun, created another path. A type 3 transaction now carries blobs, packets of data that circulate in the consensus layer. Smart contracts cannot read their content. They only access a cryptographic fingerprint of each blob, called “versioned hash.”
Blobs also have their own fee market, separate from the usual gas. Their price mainly depends on the demand for blobs. Since Fusaka, however, it cannot fall below a floor related to execution fees, under EIP-7918.
The EIP-4844 sets the window at 4,096 epochs. An epoch has 32 slots of 12 seconds. The 4,096 epochs thus represent 1,572,864 seconds, about 18.2 days. During this period, nodes must be able to provide blobs, or since Fusaka their fragments, to those who request them. Beyond this, nothing obliges them to keep Ethereum blobs.
The specification assumes this choice: “blobs aren’t expected to be stored as long as execution data of a block”. However, the official Ethereum documentation clarifies the scope of this window.
It’s a service obligation rather than a deletion date.
Ethereum.org, page dedicated to ZK rollups
The same page adds that longer-term access depends on archiving services. So a blob doesn’t erase everywhere after 18 days. It simply stops being guaranteed by the protocol.
According to Blobscan, the first blob on the network dates from March 13, 2024 at 13:55 UTC. It is included in block 19,426,589. On the Etherscan explorer, its transaction remains visible and shows a type 3 with a blob. This trace belongs to Ethereum’s permanent history.
The content itself followed another path. According to the Blobscan archive, consulted on October 27, 2026, this blob of 131,072 bytes only used 8,745 of them. Blobscan then indicated three storage locations: at Google, on the WeaveVM network, and on IPFS. The IPFS link pointed to a binary file that day.
This test illustrates the rule of Ethereum blobs. The blob’s reference remains in the chain, but its content is no longer guaranteed except by independent archivists. Without them, the fingerprint alone does not allow reconstructing the data.
Ethereum documentation compares different ways to store data on the network. The table below is inspired by it.
Data Where It Is Located After 18 Days Type 3 transaction and blob hashes Chain history Preserved, like any transaction Raw content of a blob Consensus layer, then possible archives No longer guaranteed by network nodes Calldata of a classic transaction Chain history Preserved, with no time limit State of a smart contract Chain storage Preserved until modifiedAccording to this page on storage strategies, blobs thus serve for data meant to be available for a time. Rollups use them to make their transactions available during verification, not for archiving.
The Fusaka upgrade, activated December 3, 2025, introduced PeerDAS. With this protocol, an ordinary node no longer downloads all blobs. It verifies their availability by sampling, querying fragments. According to ethereum.org, half the data is enough to reconstruct all.
This saving allowed increasing the number of blobs per block. The Fusaka announcement by the Ethereum Foundation planned two stages. On December 9, 2025, the maximum rose from 9 to 15 blobs per block. On January 7, 2026, it reached 21, with a target of 14.
However, the retention window did not change. The Fusaka specifications set 4,096 epochs as the duration during which a node must provide its data fragments. This is the same value as when blobs arrived.
Since January 7, 2026, each Ethereum block can contain up to 21 blobs. Each remains guaranteed for 4,096 epochs, about 18 days. Their price follows its own market, governed by execution fees. Our guide on Ethereum transaction fees explains these.
