Builder Registry

curl --request POST \
  --url https://beaconcha.in/api/v2/ethereum/builders \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "chain": "hoodi",
  "builder": {
    "builder_index": 1889
  },
  "page_size": 10
}
'

import requests

url = "https://beaconcha.in/api/v2/ethereum/builders"

payload = {
    "chain": "hoodi",
    "builder": { "builder_index": 1889 },
    "page_size": 10
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({chain: 'hoodi', builder: {builder_index: 1889}, page_size: 10})
};

fetch('https://beaconcha.in/api/v2/ethereum/builders', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://beaconcha.in/api/v2/ethereum/builders",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'chain' => 'hoodi',
    'builder' => [
        'builder_index' => 1889
    ],
    'page_size' => 10
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://beaconcha.in/api/v2/ethereum/builders"

	payload := strings.NewReader("{\n  \"chain\": \"hoodi\",\n  \"builder\": {\n    \"builder_index\": 1889\n  },\n  \"page_size\": 10\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://beaconcha.in/api/v2/ethereum/builders")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"chain\": \"hoodi\",\n  \"builder\": {\n    \"builder_index\": 1889\n  },\n  \"page_size\": 10\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://beaconcha.in/api/v2/ethereum/builders")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"chain\": \"hoodi\",\n  \"builder\": {\n    \"builder_index\": 1889\n  },\n  \"page_size\": 10\n}"

response = http.request(request)
puts response.read_body

{
  "data": [
    {
      "builder_index": 1889,
      "builder_pubkey": "0xa0df2d753f8a123bb822a90e421a552c28008778920345a0510a22a346c25fc7c60bfc8c1f9cfd9b7ecd945fdcef68d3",
      "builder_execution_address": "0x388C818CA8B9251b393131C08a736A67ccB19297",
      "deposit_epoch": 1,
      "superseded_epoch": 1,
      "withdrawable_epoch": 1,
      "status": "active",
      "balance": "32000000000000000000",
      "pending_balance": "32000000000000000000",
      "snapshot_slot": 1
    }
  ],
  "paging": {
    "next_cursor": "eyJfc2FtcGxlX2N1cnNvciI6MTIzNDU2Nzg5MH0"
  }
}

{
  "error": "Bad request. Please check your input and try again."
}

{
  "error": "Unauthorized. Please provide a valid API key."
}

{
  "error": "endpoint not allowed for your subscription tier. upgrade your subscription at https://beaconcha.in/pricing."
}

{
  "error": "The requested resource was not found."
}

{
  "error": "method not allowed: GET. all public API endpoints use POST."
}

{
  "error": "Rate limit exceeded. Please try again later."
}

{
  "error": "internal server error. please try again later."
}

{
  "error": "An unexpected error occurred."
}

Builders

Builder Registry

Returns the beacon chain’s builder registry, which exists from the Glamsterdam hard fork on: one row per tenure, the period in which one builder public key held one builder index, newest deposit_epoch first. Select builders with builder, or omit it to page through the whole registry; status narrows the result to one builder status.

When a builder exits and withdraws its whole balance, the chain gives its index to the next new builder, so one index can name different builders over time, and a public key that registers again can get a different index. Use builder_pubkey, not builder_index, to follow one builder. A proposal belongs to a tenure when its accepted bid names builder_index in an epoch from deposit_epoch up to, but not including, superseded_epoch.

beaconcha.in reads the registry from the finalized state at each new finalized checkpoint, so every row is a finalized snapshot, taken at its snapshot_slot. A tenure that has been superseded keeps the balance and status last observed while it held the index. Balances are stored in Gwei and returned in wei. A new builder appears once its registration is in a finalized state that beaconcha.in has read.

Combine this endpoint with others for deeper insights:

The proposals each builder won, with the payload and payment of each: 💎 v2/ethereum/builders/proposal-slots with the same builder selector
The delivery and settlement record of a builder over a window: 💎 v2/ethereum/builders/performance-aggregate
The curated operator of each builder: 💎 v2/ethereum/builders/metadata

Results are paginated with a default and maximum page size of 10.

POST

api

ethereum

builders

Builder Registry

curl --request POST \
  --url https://beaconcha.in/api/v2/ethereum/builders \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "chain": "hoodi",
  "builder": {
    "builder_index": 1889
  },
  "page_size": 10
}
'

import requests

url = "https://beaconcha.in/api/v2/ethereum/builders"

payload = {
    "chain": "hoodi",
    "builder": { "builder_index": 1889 },
    "page_size": 10
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({chain: 'hoodi', builder: {builder_index: 1889}, page_size: 10})
};

fetch('https://beaconcha.in/api/v2/ethereum/builders', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://beaconcha.in/api/v2/ethereum/builders",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'chain' => 'hoodi',
    'builder' => [
        'builder_index' => 1889
    ],
    'page_size' => 10
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://beaconcha.in/api/v2/ethereum/builders"

	payload := strings.NewReader("{\n  \"chain\": \"hoodi\",\n  \"builder\": {\n    \"builder_index\": 1889\n  },\n  \"page_size\": 10\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://beaconcha.in/api/v2/ethereum/builders")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"chain\": \"hoodi\",\n  \"builder\": {\n    \"builder_index\": 1889\n  },\n  \"page_size\": 10\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://beaconcha.in/api/v2/ethereum/builders")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"chain\": \"hoodi\",\n  \"builder\": {\n    \"builder_index\": 1889\n  },\n  \"page_size\": 10\n}"

response = http.request(request)
puts response.read_body

{
  "data": [
    {
      "builder_index": 1889,
      "builder_pubkey": "0xa0df2d753f8a123bb822a90e421a552c28008778920345a0510a22a346c25fc7c60bfc8c1f9cfd9b7ecd945fdcef68d3",
      "builder_execution_address": "0x388C818CA8B9251b393131C08a736A67ccB19297",
      "deposit_epoch": 1,
      "superseded_epoch": 1,
      "withdrawable_epoch": 1,
      "status": "active",
      "balance": "32000000000000000000",
      "pending_balance": "32000000000000000000",
      "snapshot_slot": 1
    }
  ],
  "paging": {
    "next_cursor": "eyJfc2FtcGxlX2N1cnNvciI6MTIzNDU2Nzg5MH0"
  }
}

{
  "error": "Bad request. Please check your input and try again."
}

{
  "error": "Unauthorized. Please provide a valid API key."
}

{
  "error": "endpoint not allowed for your subscription tier. upgrade your subscription at https://beaconcha.in/pricing."
}

{
  "error": "The requested resource was not found."
}

{
  "error": "method not allowed: GET. all public API endpoints use POST."
}

{
  "error": "Rate limit exceeded. Please try again later."
}

{
  "error": "internal server error. please try again later."
}

{
  "error": "An unexpected error occurred."
}

Experimental. This endpoint returns data only on chains past the Glamsterdam hard fork. Hoodi forks first; mainnet returns 404 until it forks. The request and response may change before the mainnet release. See Glamsterdam API.

Authorizations

Authorization

string

header

required

Authorization header with value: Bearer YOUR_TOKEN. Refer to the API Keys section to create your API key.

Body

application/json

chain

enum<string>

default:mainnet

The Ethereum chain to query.

Available options:

mainnet,

hoodi

builder

Builder Public Key · object

Optional builder selector. If left null, the whole builder registry is returned.

Free selectors available to all users:

builder_pubkey: One builder, by its public key, as in execution_payload.builder_pubkey. The best way to follow one builder over time.
builder_index: The builder that holds this index now. To select the builder of a past slot, use that slot's builder_pubkey.

Premium selectors for Scale & Enterprise plans (https://beaconcha.in/pricing):

builder_execution_address: Every builder that withdraws to this execution layer address. Use it for all the builders of one operator.
builder_entity: Every builder that withdraws to an address that beaconcha.in curated under this name. Optionally include builder_sub_entity. Matching is case-sensitive.

Note: Every option resolves to builder public keys, each with every period in which it held an index. An option that matches no builder returns 404. A matched builder whose tenures status filters out returns an empty list.

Builder Public Key
Builder Index
💎 Builder Execution Address
💎 Builder Entity

Show child attributes

status

enum<string>

Optional. Return only the tenures whose status is this one. Tenures with a null status never match.

Available options:

pending,

active,

exited

Example:

"active"

cursor

string

default:""

Cursor value for pagination. See our pagination guide for more details.

page_size

integer

default:10

The number of items to return per page.

Required range: 1 <= x <= 10

Response

Successful response.

Response containing the tenures in the beacon chain's builder registry, newest first.

data

object[]

required

Show child attributes

paging

object

Show child attributes

Introduction

V2 API Docs

V1 API Docs

Builder Registry

Authorizations

Body

Response