eth_blockNumber | Arc RPC Docs

Get the current block height on Arc. Essential for syncing dApps, monitoring transaction confirmations, and blockchain state tracking.

Returns the number of the most recent block on Arc.

Why Arc? Build on Circle's stablecoin-native Layer 1 where USDC is the gas token and BFT consensus gives sub-second deterministic finality with USDC as the native gas token, sub-second irreversible finality, an EWMA-smoothed fee market with a 20 Gwei floor, and EIP-7708 Transfer logs for native value movement.

When to Use This Method

eth_blockNumber is fundamental for payment platforms, stablecoin issuers, exchange and treasury teams, and Solidity developers building on Arc:

Syncing Applications - Keep your dApp in sync with the latest Arc blockchain state
Transaction Monitoring - Verify confirmations by comparing block numbers
Event Filtering - Set the correct block range for querying logs on crossborder settlement, merchant payments, institutional clearing, and USDC-denominated financial applications
Health Checks - Monitor node connectivity and sync status

Common Use Cases

1. Block Confirmation Counter

Monitor transaction confirmations on Arc:

JavaScript

async function getConfirmations(provider, txHash) {
  const tx = await provider.getTransaction(txHash);
  if (!tx || !tx.blockNumber) return 0;

  const currentBlock = await provider.getBlockNumber();
  return currentBlock - tx.blockNumber + 1;
}

// Wait for specific confirmations
async function waitForConfirmations(provider, txHash, confirmations = 6) {
  let currentConfirmations = 0;

  while (currentConfirmations < confirmations) {
    currentConfirmations = await getConfirmations(provider, txHash);
    console.log(`Confirmations: ${currentConfirmations}/${confirmations}`);
    await new Promise(r => setTimeout(r, 2000));
  }

  return true;
}

2. Event Log Filtering

Query events from recent blocks on Arc:

JavaScript

async function getRecentEvents(provider, contract, eventName, blockRange = 100) {
  const currentBlock = await provider.getBlockNumber();
  const fromBlock = currentBlock - blockRange;

  const filter = contract.filters[eventName]();
  const events = await contract.queryFilter(filter, fromBlock, currentBlock);

  return events;
}

3. Node Health Monitoring

Check if your Arc node is synced:

JavaScript

async function checkNodeHealth(provider) {
  try {
    const blockNumber = await provider.getBlockNumber();
    const block = await provider.getBlock(blockNumber);

    const now = Date.now() / 1000;
    const blockAge = now - block.timestamp;

    if (blockAge > 60) {
      console.warn(`Node may be behind. Last block was ${blockAge}s ago`);
      return false;
    }

    console.log(`Node healthy. Latest block: ${blockNumber}`);
    return true;
  } catch (error) {
    console.error('Node unreachable:', error);
    return false;
  }
}

Performance Optimization

Caching Strategy

Cache block numbers to reduce API calls:

JavaScript

class BlockNumberCache {
  constructor(ttl = 2000) {
    this.cache = null;
    this.timestamp = 0;
    this.ttl = ttl;
  }

  async get(provider) {
    const now = Date.now();

    if (this.cache && (now - this.timestamp) < this.ttl) {
      return this.cache;
    }

    this.cache = await provider.getBlockNumber();
    this.timestamp = now;
    return this.cache;
  }

  invalidate() {
    this.cache = null;
    this.timestamp = 0;
  }
}

const blockCache = new BlockNumberCache();

Batch Requests

Combine with other calls for efficiency:

JavaScript

const batch = [
  { jsonrpc: '2.0', method: 'eth_blockNumber', params: [], id: 1 },
  { jsonrpc: '2.0', method: 'eth_gasPrice', params: [], id: 2 },
  { jsonrpc: '2.0', method: 'eth_chainId', params: [], id: 3 }
];

const response = await fetch('https://api-arc-mainnet.n.dwellir.com/YOUR_API_KEY', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify(batch)
});

const results = await response.json();

Arc uses Malachite, a Tendermint-style BFT consensus with a Proof-of-Authority validator set. A block is committed only after more than two-thirds of validators pre-commit to it, which makes conflicting blocks impossible and rules out reorganizations entirely.

A transaction is therefore either unconfirmed or final, with no probabilistic middle ground. One confirmation is enough. Once you have a receipt, settlement is irreversible in under a second.

For integrations this means you can drop the machinery that probabilistic chains require: no confirmation-count thresholds, no reorg rollback path, no re-org-aware bookkeeping. Persist the block number and hash for auditability, then act on the receipt.

Error Handling

Common errors and solutions:

Error Code	Description	Solution
-32603	Internal error	Retry with exponential backoff
-32005	Rate limit exceeded	Implement rate limiting client-side
-32000	Execution reverted	Check node sync status

JavaScript

async function safeGetBlockNumber(provider, maxRetries = 3) {
  for (let i = 0; i < maxRetries; i++) {
    try {
      return await provider.getBlockNumber();
    } catch (error) {
      if (error.code === -32005) {
        await new Promise(r => setTimeout(r, Math.pow(2, i) * 1000));
      } else if (i === maxRetries - 1) {
        throw error;
      }
    }
  }
}

eth_getBlockByNumber - Get full block details by number
eth_getBlockByHash - Get block details by hash
eth_syncing - Check if node is still syncing

Returns the number of the most recent block on Arc.

Why Arc? Build on Circle's stablecoin-native Layer 1 where USDC is the gas token and BFT consensus gives sub-second deterministic finality with USDC as the native gas token, sub-second irreversible finality, an EWMA-smoothed fee market with a 20 Gwei floor, and EIP-7708 Transfer logs for native value movement.

When to Use This Method

eth_blockNumber is fundamental for payment platforms, stablecoin issuers, exchange and treasury teams, and Solidity developers building on Arc:

Syncing Applications - Keep your dApp in sync with the latest Arc blockchain state
Transaction Monitoring - Verify confirmations by comparing block numbers
Event Filtering - Set the correct block range for querying logs on crossborder settlement, merchant payments, institutional clearing, and USDC-denominated financial applications
Health Checks - Monitor node connectivity and sync status

async function getConfirmations(provider, txHash) {
  const tx = await provider.getTransaction(txHash);
  if (!tx || !tx.blockNumber) return 0;

  const currentBlock = await provider.getBlockNumber();
  return currentBlock - tx.blockNumber + 1;
}

// Wait for specific confirmations
async function waitForConfirmations(provider, txHash, confirmations = 6) {
  let currentConfirmations = 0;

  while (currentConfirmations < confirmations) {
    currentConfirmations = await getConfirmations(provider, txHash);
    console.log(`Confirmations: ${currentConfirmations}/${confirmations}`);
    await new Promise(r => setTimeout(r, 2000));
  }

  return true;
}

2. Event Log Filtering

Query events from recent blocks on Arc:

JavaScript

async function getRecentEvents(provider, contract, eventName, blockRange = 100) {
  const currentBlock = await provider.getBlockNumber();
  const fromBlock = currentBlock - blockRange;

  const filter = contract.filters[eventName]();
  const events = await contract.queryFilter(filter, fromBlock, currentBlock);

  return events;
}

3. Node Health Monitoring

Check if your Arc node is synced:

JavaScript

async function checkNodeHealth(provider) {
  try {
    const blockNumber = await provider.getBlockNumber();
    const block = await provider.getBlock(blockNumber);

    const now = Date.now() / 1000;
    const blockAge = now - block.timestamp;

    if (blockAge > 60) {
      console.warn(`Node may be behind. Last block was ${blockAge}s ago`);
      return false;
    }

    console.log(`Node healthy. Latest block: ${blockNumber}`);
    return true;
  } catch (error) {
    console.error('Node unreachable:', error);
    return false;
  }
}

Performance Optimization

Caching Strategy

Cache block numbers to reduce API calls:

JavaScript

class BlockNumberCache {
  constructor(ttl = 2000) {
    this.cache = null;
    this.timestamp = 0;
    this.ttl = ttl;
  }

  async get(provider) {
    const now = Date.now();

    if (this.cache && (now - this.timestamp) < this.ttl) {
      return this.cache;
    }

    this.cache = await provider.getBlockNumber();
    this.timestamp = now;
    return this.cache;
  }

  invalidate() {
    this.cache = null;
    this.timestamp = 0;
  }
}

const blockCache = new BlockNumberCache();

Batch Requests

Combine with other calls for efficiency:

JavaScript

const batch = [
  { jsonrpc: '2.0', method: 'eth_blockNumber', params: [], id: 1 },
  { jsonrpc: '2.0', method: 'eth_gasPrice', params: [], id: 2 },
  { jsonrpc: '2.0', method: 'eth_chainId', params: [], id: 3 }
];

const response = await fetch('https://api-arc-mainnet.n.dwellir.com/YOUR_API_KEY', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify(batch)
});

const results = await response.json();

Finality on Arc

A transaction is therefore either unconfirmed or final, with no probabilistic middle ground. One confirmation is enough. Once you have a receipt, settlement is irreversible in under a second.

Error Handling

Common errors and solutions:

Error Code	Description	Solution
-32603	Internal error	Retry with exponential backoff
-32005	Rate limit exceeded	Implement rate limiting client-side
-32000	Execution reverted	Check node sync status

JavaScript

async function safeGetBlockNumber(provider, maxRetries = 3) {
  for (let i = 0; i < maxRetries; i++) {
    try {
      return await provider.getBlockNumber();
    } catch (error) {
      if (error.code === -32005) {
        await new Promise(r => setTimeout(r, Math.pow(2, i) * 1000));
      } else if (i === maxRetries - 1) {
        throw error;
      }
    }
  }
}

eth_getBlockByNumber - Get full block details by number
eth_getBlockByHash - Get block details by hash
eth_syncing - Check if node is still syncing

eth_blockNumber - Arc RPC Method

When to Use This Method

Code Examples

Common Use Cases

1. Block Confirmation Counter

2. Event Log Filtering

3. Node Health Monitoring

Performance Optimization

Caching Strategy

Batch Requests

Finality on Arc

Error Handling

On this page

eth_blockNumber - Arc RPC Method

When to Use This Method

Code Examples

Common Use Cases

1. Block Confirmation Counter

2. Event Log Filtering

3. Node Health Monitoring

Performance Optimization

Caching Strategy

Batch Requests

Finality on Arc

Error Handling

On this page