Attestation data


The interactive example will return Slot already finalized unless you edit the parameters.

The /eth/v1/validator/attestation_data method is an essential API endpoint in the Ethereum Beacon Chain, primarily used by validators. This method provides the necessary data for validators to create an attestation—a process where validators confirm and endorse a particular block's data. Attestations are fundamental in the Ethereum PoS protocol, as they contribute to the consensus and validation of the blockchain.

This endpoint is crucial for validators who need to fetch the latest data to attest to the state of the blockchain effectively.


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  • none


  • object — attestation data.
    • slot — the slot number for which the attestation is being made. In the Ethereum Beacon Chain, a slot is a period during which new blocks can be proposed and attested.
    • committee_index — the index of the committee to which the validator belongs. This index indicates the group of validators responsible for attesting to a specific shard or part of the blockchain.
    • beacon_block_root — the root of the beacon block that the attestation is targeting. This root acts as an identifier for the specific block being attested.
    • source — the source checkpoint of the attestation. This includes the epoch and the root of the block at the start of the epoch.
    • target — the target checkpoint of the attestation. Similar to the source, this includes the epoch and the block root, but for the end of the attestation period.

The /eth/v1/validator/attestation_data method is a key tool for validators in the Ethereum network. It enables them to participate actively in the consensus process, ensuring the blockchain's integrity and continuous validation.

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