Node API
Supported Chains
API Reference
Ethereum Beacon

Ethereum Beacon


Available for Premium users only.

Ethereum Beacon API is available on Web3 API platform (opens in a new tab) upon switching on the Beacon toggle.

The Beacon Chain is a consensus layer that introduced a proof-of-stake (opens in a new tab) to Ethereum. The Beacon Chain mechanism is responsible for creating new blocks, making sure those new blocks are valid, and rewarding validators with ETH for keeping the network secure.

In order for your Web3 application to interact with the Beacon Chain — either by reading blockchain data or sending transactions to the network — it must connect to a Beacon node. Developers interact with the blockchain using the methods provided by the API.

Beacon API uses the REST interface for querying, responses come in JSON format (opens in a new tab).

Methods supported

Beacon:

Builder:

Config:

Debug:

Events:

Node:

Validator:

ValidatorRequiredApi:

Rewards:

Beacon

GET /eth/v1/beacon/genesis

Retrieves the details of the chain's genesis.

Returns the details of the chain's genesis which can be used to identify chain.

Parameters

None.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/genesis" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "data": {
    "genesis_time": "1590832934",
    "genesis_validators_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
    "genesis_fork_version": "0x00000000"
  }
}
  • 400: Chain genesis info is not yet known.
{
  "code": 404,
  "message": "Chain genesis info is not yet known"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/root

Retrieves the state SSZ HashTreeRoot.

Calculates HashTreeRoot for state with given 'stateId'. If stateId is root, same value will be returned.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.
    Example: head.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/root" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": {
    "root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"
  }
}
  • 400: Invalid state ID.
{
  "code": 400,
  "message": "Invalid state ID: current"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/fork

Retrieves the Fork object for a requested state.

Retrieves the Fork (opens in a new tab) object for state with given 'stateId'.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/fork" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "data": {
    "previous_version": "0x00000000",
    "current_version": "0x00000000",
    "epoch": "1"
  }
}
  • 400: Invalid state ID.
{
  "code": 400,
  "message": "Invalid state ID: current"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/finality_checkpoints

Retrieves state finality checkpoints.

Returns finality checkpoints for state with given 'stateId'. In case finality is not yet achieved, checkpoint should return epoch 0 and ZERO_HASH as root.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/finality_checkpoints" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": {
    "previous_justified": {
      "epoch": "1",
      "root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"
    },
    "current_justified": {
      "epoch": "1",
      "root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"
    },
    "finalized": {
      "epoch": "1",
      "root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"
    }
  }
}
  • 400: Invalid state ID.
{
  "code": 400,
  "message": "Invalid state ID: current"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/validators

Retrieves validators from state.

Returns filterable list of validators with their balance, status, and index.

Information will be returned for all indices or public key that match known validators. If an index or public key does not match any known validator, no information will be returned but this will not cause an error. There are no guarantees for the returned data in terms of ordering; both the index and public key are returned for each validator, and can be used to confirm for which inputs a response has been returned.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.
  • id (array[string]; query): either a hex encoded public key (any bytes48 with 0x prefix) or validator index.
  • status (array; query): see the validator status specification (opens in a new tab).

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your-token}/eth/v1/beacon/states/{state_id}/validators" \
-H "Accept: application/json"

Responses

  • 200: Success
{
  "execution_optimistic": false,
  "finalized": false,
  "data": [
    {
      "index": "1",
      "balance": "1",
      "status": "active_ongoing",
      "validator": {
        "pubkey": "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a",
        "withdrawal_credentials": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
        "effective_balance": "1",
        "slashed": false,
        "activation_eligibility_epoch": "1",
        "activation_epoch": "1",
        "exit_epoch": "1",
        "withdrawable_epoch": "1"
      }
    }
  ]
}
  • 400: Invalid state or validator ID, or status.
{
  "code": 400,
  "message": "Invalid state ID: current"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 414: Too many validator IDs.
{
  "code": 414,
  "message": "Too many validator IDs in request"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

POST /eth/v1/beacon/states/{state_id}/validators

Retrieves validators from state.

Returns filterable list of validators with their balance, status and index.

Information will be returned for all indices or public key that match known validators. If an index or public key does not match any known validator, no information will be returned but this will not cause an error. There are no guarantees for the returned data in terms of ordering; both the index and public key are returned for each validator, and can be used to confirm for which inputs a response has been returned.

The POST variant of this endpoint has the same semantics as the GET endpoint but passes the lists of IDs and statuses via a POST body in order to enable larger requests.

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.

  • <request body> (required): The lists of validator IDs and statuses to filter on. Either or both may be null to signal that no filtering on that attribute is desired.

{
  "ids": [
    "string"
  ],
  "statuses": [
    "active_ongoing"
  ]
}

Request example

curl -X POST "https://rpc.ankr.com/premium-http/eth_beacon/{your-token}/eth/v1/beacon/states/{state_id}/validators" \
-H "Accept: application/json"
-d '{
  "ids": [
    "string"
  ],
  "statuses": [
    "active_ongoing"
  ]
}'

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": [
    {
      "index": "1",
      "balance": "1",
      "status": "active_ongoing",
      "validator": {
        "pubkey": "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a",
        "withdrawal_credentials": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
        "effective_balance": "1",
        "slashed": false,
        "activation_eligibility_epoch": "1",
        "activation_epoch": "1",
        "exit_epoch": "1",
        "withdrawable_epoch": "1"
      }
    }
  ]
}
  • 400: Invalid state or validator ID, or status.
{
  "code": 400,
  "message": "Invalid state ID: current"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/validators/{validator_id}

Retrieves the validator from state by ID.

Returns validator specified by state and id or public key along with status and balance.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.
  • validator_id (string; path; required): either a hex encoded public key (any bytes48 with 0x prefix) or validator index.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/validators/{validator_id}" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": {
    "index": "1",
    "balance": "1",
    "status": "active_ongoing",
    "validator": {
      "pubkey": "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a",
      "withdrawal_credentials": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
      "effective_balance": "1",
      "slashed": false,
      "activation_eligibility_epoch": "1",
      "activation_epoch": "1",
      "exit_epoch": "1",
      "withdrawable_epoch": "1"
    }
  }
}
  • 400: Invalid state or validator ID, or status.
{
  "code": 400,
  "message": "Invalid state ID: current"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/validator_balances

Retrieves validator balances from state.

Returns filterable list of validators balances.

Balances will be returned for all indices or public key that match known validators. If an index or public key does not match any known validator, no balance will be returned but this will not cause an error. There are no guarantees for the returned data in terms of ordering; the index and is returned for each balance, and can be used to confirm for which inputs a response has been returned.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.
  • id (array[string]; query): either a hex encoded public key (any bytes48 with 0x prefix) or validator index.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/validator_balances" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": [
    {
      "index": "1",
      "balance": "1"
    }
  ]
}
  • 400: Invalid state or validator ID, or status.
{
  "code": 400,
  "message": "Invalid state ID: current"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 414: Too many validator IDs.
{
  "code": 414,
  "message": "Too many validator IDs in request"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

POST /eth/v1/beacon/states/{state_id}/validator_balances

Retrieves validator balances from state.

Returns filterable list of validators balances.

Balances will be returned for all indices or public key that match known validators. If an index or public key does not match any known validator, no balance will be returned but this will not cause an error. There are no guarantees for the returned data in terms of ordering; the index is returned for each balance, and can be used to confirm for which inputs a response has been returned.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.
  • <request body>: an array of either hex encoded public key (any bytes48 with 0x prefix) or validator index.
[
  "string"
]

Request example

curl -X POST "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/validator_balances" \
  -H 'Accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '[
  "string"
]'

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": [
    {
      "index": "1",
      "balance": "1"
    }
  ]
}
  • 400: Invalid state or validator ID, or status.
{
  "code": 400,
  "message": "Invalid state ID: current"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/committees

Retrieves all committees for a state.

Retrieves the committees for the given state.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.
  • epoch (string; query): fetches committees for the given epoch; if not present then the committees for the epoch of the state will be obtained.
  • index (string; query): restricts returned values to those matching the supplied committee index.
  • slot (string; query): restricts returned values to those matching the supplied slot.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/committees" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": [
    {
      "index": "1",
      "slot": "1",
      "validators": [
        "1"
      ]
    }
  ]
}
  • 400: Invalid state ID, index, epoch, slot, or combination thereof.
{
  "code": 400,
  "message": "Slot does not belong in epoch"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/sync_committees

Retrieves sync committees for a state.

Retrieves the current sync committee for the given state. Also returns the subcommittee assignments.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.
  • epoch (string; query): fetches sync committees for the given epoch; if not present then the sync committees for the epoch of the state will be obtained.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/sync_committees" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": {
    "validators": [
      "1"
    ],
    "validator_aggregates": [
      [
        "1"
      ]
    ]
  }
}
  • 400: Invalid state ID, index, epoch, slot, or combination thereof.
{
  "code": 400,
  "message": "Slot does not belong in epoch"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/states/{state_id}/randao

Retrieves the RANDAO mix for some epoch in a specified state.

Fetch the RANDAO mix for the requested epoch from the state identified by state_id.

If an epoch is not specified then the RANDAO mix for the state's current epoch will be returned.

By adjusting the state_id parameter you can query for any historic value of the RANDAO mix. Ordinarily states from the same epoch will mutate the RANDAO mix for that epoch as blocks are applied.

Parameters

  • state_id (string; path; required): state identifier. Can be one of: head (canonical head in node's view), genesis, finalized, justified, <slot>, <hex encoded stateRoot with 0x prefix>.
  • epoch (string; query): fetches sync committees for the given epoch; if not present then the sync committees for the epoch of the state will be obtained.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/states/{state_id}/randao" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": {
    "randao": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"
  }
}
  • 400: Invalid state ID or epoch.
{
  "code": 400,
  "message": "Epoch is out of range for the `randao_mixes` of the state"
}
  • 404: State not found.
{
  "code": 404,
  "message": "State not found"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/headers

Retrieves block headers.

Retrieves block headers matching given query. By default, it will fetch current head slot blocks.

Parameters

  • slot (string; query): a slot.
  • parent_root (string, hex; query): a parent root.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/headers" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": [
    {
      "root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
      "canonical": true,
      "header": {
        "message": {
          "slot": "1",
          "proposer_index": "1",
          "parent_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
          "state_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
          "body_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"
        },
        "signature": "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"
      }
    }
  ]
}
  • 400: The block ID supplied could not be parsed.
{
  "code": 400,
  "message": "Invalid block ID: current"
}
  • 500: Beacon node internal error.
{
  "code": 500,
  "message": "Internal server error"
}

GET /eth/v1/beacon/headers/{block_id}

Retrieves a block header.

Retrieves a block header for a given block ID.

Parameters

  • block_id (string; path; required): a block identifier. Can be one of: head (canonical head in node's view), genesis, finalized, <slot>, <hex encoded blockRoot with 0x prefix>.

Request example

curl -X GET "https://rpc.ankr.com/premium-http/eth_beacon/{your_token}/eth/v1/beacon/headers/{block_id}" \
-H "Accept: application/json"

Responses

  • 200: Success.
{
  "execution_optimistic": false,
  "finalized": false,
  "data": {
    "root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
    "canonical": true,
    "header": {
      "message": {
        "slot": "1",
        "proposer_index": "1",
        "parent_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
        "state_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
        "body_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"
      },
      "signature": "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"
    }
  }
}
  • 400: The block ID supplied could not be parsed.
{
  "code": 400,
  "message": "Invalid block ID: current"
}
  • 404: Block not found.
{
  "code": 404,
  "message": "Block not found"
}
  • 500: Beacon node internal error.