Chain Information

Access comprehensive blockchain metadata, RPC endpoints, and cross-chain data.

Try it Live

Open in Swagger UI → to test these endpoints interactively.

Endpoints

Endpoint	Description	Price
`GET /api/chains`	List all chains	FREE
`GET /api/chains/:id`	Chain details	FREE
`GET /api/chains/:id/status`	Chain status	FREE
`GET /api/chains/:id/blocks`	Recent blocks	$0.005

GET /api/chains

List all supported blockchains.

Request

curl https://api.web3identity.com/api/chains

Response

{
  "chains": [
    {
      "id": 1,
      "name": "Ethereum",
      "shortName": "eth",
      "network": "mainnet",
      "nativeCurrency": {
        "name": "Ether",
        "symbol": "ETH",
        "decimals": 18
      },
      "rpc": ["https://eth.llamarpc.com"],
      "explorers": [
        {
          "name": "Etherscan",
          "url": "https://etherscan.io",
          "standard": "EIP3091"
        }
      ],
      "features": ["ENS", "EIP1559", "EIP4844"],
      "testnet": false
    },
    {
      "id": 8453,
      "name": "Base",
      "shortName": "base",
      "network": "mainnet",
      "nativeCurrency": {
        "name": "Ether",
        "symbol": "ETH",
        "decimals": 18
      },
      "rpc": ["https://mainnet.base.org"],
      "parentChain": 1,
      "l2Type": "optimistic",
      "testnet": false
    }
  ],
  "count": 45,
  "categories": {
    "mainnet": 35,
    "testnet": 10,
    "l2": 12,
    "sidechain": 3
  }
}

GET /api/chains/:id

Get detailed information for a specific chain.

Request

curl https://api.web3identity.com/api/chains/1

Response

{
  "id": 1,
  "name": "Ethereum",
  "shortName": "eth",
  "network": "mainnet",
  "chainType": "L1",
  "nativeCurrency": {
    "name": "Ether",
    "symbol": "ETH",
    "decimals": 18
  },
  "rpc": [
    "https://eth.llamarpc.com",
    "https://ethereum.publicnode.com",
    "https://rpc.ankr.com/eth"
  ],
  "wss": [
    "wss://ethereum.publicnode.com"
  ],
  "explorers": [
    {
      "name": "Etherscan",
      "url": "https://etherscan.io",
      "standard": "EIP3091",
      "apiUrl": "https://api.etherscan.io/api"
    }
  ],
  "consensus": "PoS",
  "blockTime": 12,
  "gasToken": "ETH",
  "features": {
    "ens": true,
    "eip1559": true,
    "eip4844": true,
    "multicall": "0xcA11bde05977b3631167028862bE2a173976CA11"
  },
  "bridges": [
    {
      "name": "Arbitrum Bridge",
      "url": "https://bridge.arbitrum.io",
      "chains": [42161]
    },
    {
      "name": "Optimism Bridge",
      "url": "https://app.optimism.io/bridge",
      "chains": [10]
    }
  ],
  "faucets": [],
  "testnet": false,
  "infoUrl": "https://ethereum.org",
  "status": "active"
}

GET /api/chains/:id/status

Get real-time chain status and health.

Request

curl https://api.web3identity.com/api/chains/1/status

Response

{
  "chain": "Ethereum",
  "chainId": 1,
  "status": "healthy",
  "currentBlock": 19234567,
  "blockTime": 12.1,
  "avgBlockTime24h": 12.05,
  "gasPrice": {
    "fast": 35,
    "standard": 28,
    "slow": 22
  },
  "tps": 15.2,
  "pendingTransactions": 89234,
  "difficulty": "58750003716598352816469",
  "hashrate": "892.5 TH/s",
  "validators": 987234,
  "stakedETH": "32456789",
  "lastUpdate": "2026-02-08T12:34:56Z",
  "health": {
    "rpcLatency": 45,
    "blockLag": 0,
    "syncStatus": "synced"
  }
}

Status Values

Status	Description
`healthy`	Operating normally
`degraded`	Reduced performance
`outage`	Not responding
`syncing`	Still syncing blocks

GET /api/chains/:id/blocks

Get recent blocks for a chain.

Query Parameters

Param	Type	Default	Description
`limit`	number	10	Max blocks (1-100)
`includeTransactions`	boolean	false	Include tx hashes

Request

curl "https://api.web3identity.com/api/chains/1/blocks?limit=5"

Response

{
  "chainId": 1,
  "blocks": [
    {
      "number": 19234567,
      "hash": "0xabc123...",
      "timestamp": "2026-02-08T12:34:56Z",
      "miner": "0x...",
      "gasUsed": 15234567,
      "gasLimit": 30000000,
      "baseFee": 25.5,
      "transactionCount": 234,
      "size": 123456
    }
  ],
  "avgBlockTime": 12.1,
  "avgGasUsed": 14567890
}

Supported Chains

Mainnets

Chain	ID	Type	ENS
Ethereum	1	L1	✅
Base	8453	L2 (OP)	✅
Arbitrum One	42161	L2 (OP)	✅
Optimism	10	L2 (OP)	✅
Polygon	137	Sidechain	✅
Avalanche C-Chain	43114	L1	❌
BNB Smart Chain	56	Sidechain	❌
Gnosis	100	L1	✅
Polygon zkEVM	1101	L2 (ZK)	❌
zkSync Era	324	L2 (ZK)	❌

Testnets

Chain	ID	Faucet
Sepolia	11155111	Faucet
Base Sepolia	84532	Faucet
Arbitrum Sepolia	421614	Faucet

SDK Examples

JavaScript

import { Web3IdentityClient } from '@web3identity/sdk';

const client = new Web3IdentityClient();

// List all chains
const chains = await client.getChains();
console.log(`Supported chains: ${chains.count}`);

// Get chain details
const ethereum = await client.getChain(1);
console.log(`Block time: ${ethereum.blockTime}s`);
console.log(`Consensus: ${ethereum.consensus}`);

// Check chain status
const status = await client.getChainStatus(1);
console.log(`Current block: ${status.currentBlock}`);
console.log(`TPS: ${status.tps}`);

// Get recent blocks
const blocks = await client.getBlocks(1, { limit: 10 });
console.log(`Latest block: ${blocks.blocks[0].number}`);

React Hook

import { useState, useEffect } from 'react';

function useChainStatus(chainId: number) {
  const [status, setStatus] = useState(null);
  const [loading, setLoading] = useState(true);

  useEffect(() => {
    const fetchStatus = async () => {
      const res = await fetch(
        `https://api.web3identity.com/api/chains/${chainId}/status`
      );
      const data = await res.json();
      setStatus(data);
      setLoading(false);
    };

    fetchStatus();
    const interval = setInterval(fetchStatus, 15000); // Update every 15s

    return () => clearInterval(interval);
  }, [chainId]);

  return { status, loading };
}

// Usage
function ChainMonitor({ chainId }: { chainId: number }) {
  const { status, loading } = useChainStatus(chainId);

  if (loading) return <div>Loading...</div>;

  return (
    <div className="chain-status">
      <h3>{status.chain}</h3>
      <div className="metrics">
        <div>Block: #{status.currentBlock.toLocaleString()}</div>
        <div>TPS: {status.tps.toFixed(1)}</div>
        <div>Gas: {status.gasPrice.standard} gwei</div>
        <div>Status: <span className={status.status}>{status.status}</span></div>
      </div>
    </div>
  );
}

Python

from web3identity import Client

client = Client()

# List chains
chains = client.get_chains()
print(f"Total chains: {chains['count']}")

# Get chain info
eth = client.get_chain(1)
print(f"Chain: {eth['name']}")
print(f"Native token: {eth['nativeCurrency']['symbol']}")
print(f"RPC: {eth['rpc'][0]}")

# Check status
status = client.get_chain_status(1)
print(f"Current block: {status['currentBlock']:,}")
print(f"Block time: {status['blockTime']}s")
print(f"Gas (standard): {status['gasPrice']['standard']} gwei")

# Multi-chain comparison
def compare_chains(chain_ids):
    for chain_id in chain_ids:
        status = client.get_chain_status(chain_id)
        print(f"{status['chain']}: {status['tps']:.1f} TPS, {status['gasPrice']['standard']} gwei")

compare_chains([1, 8453, 42161, 10])

cURL Examples

# List all chains
curl https://api.web3identity.com/api/chains

# Get Ethereum details
curl https://api.web3identity.com/api/chains/1

# Get Base status
curl https://api.web3identity.com/api/chains/8453/status

# Get recent blocks
curl "https://api.web3identity.com/api/chains/1/blocks?limit=10"

# Filter chains by type
curl "https://api.web3identity.com/api/chains?type=l2"

Chain Selection Helper

// Auto-select fastest chain with lowest gas
async function selectOptimalChain(supportedChains) {
  const statuses = await Promise.all(
    supportedChains.map(id => 
      fetch(`https://api.web3identity.com/api/chains/${id}/status`)
        .then(r => r.json())
    )
  );

  // Score based on gas price and TPS
  const scored = statuses.map(s => ({
    chainId: s.chainId,
    chain: s.chain,
    score: (s.tps / 10) - (s.gasPrice.standard / 5), // Higher TPS, lower gas = better
    gas: s.gasPrice.standard,
    tps: s.tps
  }));

  // Sort by score
  scored.sort((a, b) => b.score - a.score);

  return scored[0];
}

// Usage
const optimal = await selectOptimalChain([1, 8453, 42161, 10]);
console.log(`Best chain: ${optimal.chain} (${optimal.tps} TPS, ${optimal.gas} gwei)`);

Multi-Chain Routing

Example of routing transactions based on chain availability:

class ChainRouter {
  constructor(preferredChains = [1, 8453, 42161]) {
    this.chains = preferredChains;
  }

  async getHealthyChain() {
    for (const chainId of this.chains) {
      const status = await fetch(
        `https://api.web3identity.com/api/chains/${chainId}/status`
      ).then(r => r.json());

      if (status.status === 'healthy' && status.health.blockLag < 10) {
        return {
          chainId,
          name: status.chain,
          gasPrice: status.gasPrice.standard
        };
      }
    }

    throw new Error('No healthy chains available');
  }

  async executeOnBestChain(transaction) {
    const chain = await this.getHealthyChain();
    console.log(`Routing to ${chain.name} (${chain.gasPrice} gwei)`);
    // Execute transaction
    return chain;
  }
}

const router = new ChainRouter([8453, 42161, 10, 1]); // Prefer L2s
const chain = await router.getHealthyChain();

Bridge Aggregation

Find available bridges between chains:

async function findBridges(fromChainId, toChainId) {
  const fromChain = await fetch(
    `https://api.web3identity.com/api/chains/${fromChainId}`
  ).then(r => r.json());

  const bridges = fromChain.bridges.filter(b =>
    b.chains.includes(toChainId)
  );

  return bridges.map(b => ({
    name: b.name,
    url: b.url,
    estimatedTime: b.estimatedTime || 'Unknown'
  }));
}

// Find bridges from Ethereum to Arbitrum
const bridges = await findBridges(1, 42161);
bridges.forEach(b => console.log(`${b.name}: ${b.url}`));

RPC Failover

Implement RPC failover using multiple endpoints:

async function fetchWithFailover(chainId, method, params) {
  const chain = await fetch(
    `https://api.web3identity.com/api/chains/${chainId}`
  ).then(r => r.json());

  for (const rpc of chain.rpc) {
    try {
      const response = await fetch(rpc, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          jsonrpc: '2.0',
          id: 1,
          method,
          params
        }),
        timeout: 5000
      });

      if (response.ok) {
        const data = await response.json();
        return data.result;
      }
    } catch (error) {
      console.warn(`RPC ${rpc} failed, trying next...`);
      continue;
    }
  }

  throw new Error(`All RPCs failed for chain ${chainId}`);
}

// Usage
const blockNumber = await fetchWithFailover(1, 'eth_blockNumber', []);
console.log(`Current block: ${parseInt(blockNumber, 16)}`);

Gas Prices — Gas price data
Wallet Balances — Multi-chain balances
Transaction History — Cross-chain transactions
Token Prices — Multi-chain token prices

Endpoints​

GET /api/chains​

Request​

Response​

GET /api/chains/:id​

Request​

Response​

GET /api/chains/:id/status​

Request​

Response​

Status Values​

GET /api/chains/:id/blocks​

Query Parameters​

Request​

Response​

Supported Chains​

Mainnets​

Testnets​

SDK Examples​

JavaScript​

React Hook​

Python​

cURL Examples​

Chain Selection Helper​

Multi-Chain Routing​

Bridge Aggregation​

RPC Failover​

Related Endpoints​

Endpoints

GET /api/chains

Request

Response

GET /api/chains/:id

Request

Response

GET /api/chains/:id/status

Request

Response

Status Values

GET /api/chains/:id/blocks

Query Parameters

Request

Response

Supported Chains

Mainnets

Testnets

SDK Examples

JavaScript

React Hook

Python

cURL Examples

Chain Selection Helper

Multi-Chain Routing

Bridge Aggregation

RPC Failover

Related Endpoints