Chains API

Retrieve a list of supported chains and their associated metadata.

The Blocknative Chains API provides metadata on supported chains, including their chain ID, label, architecture, and available features. This allows developers to dynamically identify which networks are integrated with Blocknative services.

Authentication

A valid Blocknative API key is OPTIONAL in the Authorization Header of every request. Request an API key here .

A free API key is recommended for more generous rate limits and future features.

API Endpoint

GET https://api.blocknative.com/chains

Returns a list of supported chains along with their chain ID, label, architecture (e.g., evm), and available features (e.g., blockprices). This allows users to identify networks where Blocknative provides gas price estimation and related services. The list and available fields are subject to change as new chains or parameters are added or updated.

Rate Limits

Each endpoint is limited to provide updated results once per second for paid tier API keys, or every 5 seconds for free tier API keys. Polling faster than these rates may deliver stale data.

Example Request

curl -H 'Authorization: optional-apikey-here'
     'https://api.blocknative.com/chains'
bash

Headers

NameTypeDescription
AuthorizationString

OPTIONAL

if used, must contain a valid apikey

Response Codes

CodeDescription
200Success
401API key invalid or not provided
429Rate limit exceeded. Refer to headers for retry

Example Response

[
  {
    "arch": "evm",
    "chainId": 1,
    "label": "Ethereum",
    "features": ["blockprices", "recentblocks", "distribution"],
    "icon": "https://bnc-assets.com/evm/1/assets/icon.svg",
    "system": "ethereum",
    "network": "mainnet"
  },
  {
    "arch": "evm",
    "chainId": 137,
    "label": "Polygon",
    "features": ["blockprices"],
    "icon": "https://bnc-assets.com/evm/137/assets/icon.svg",
    "system": "ethereum",
    "network": "mainnet"
  },
  {
    "arch": "evm",
    "chainId": 8453,
    "label": "Base",
    "features": ["blockprices"],
    "icon": "https://bnc-assets.com/evm/8453/assets/icon.svg",
    "system": "ethereum",
    "network": "mainnet"
  }
]
javascript

Response Fields

FieldTypeDescription
archStringThe blockchain architecture (e.g., "evm").
chainIdIntegerThe unique identifier for the blockchain (e.g., 1 for Ethereum).
labelStringThe human-readable name of the blockchain (e.g., "Polygon zkEVM").
featuresArray[String]List of features supported by Blocknative on this chain (e.g., ["blockprices"]).
iconStringURL to the blockchain's icon.
systemStringThe human-readable name of the ecosystem, (e.g. "ethereum" or "bitcoin")
networkStringInternal name of the blockchain (e.g. "mainnet" or "sepolia"). See chain table .

Notes

  • The list of supported blockchains and available features may change as new networks are integrated.
  • This endpoint does not include gas price data—use the /blockprices endpoint for real-time gas estimations.
Last update at: 2025/08/01 00:25:42