eth_maxPriorityFeePerGas | Arc RPC Docs

Get the suggested priority fee (tip) per gas for EIP-1559 transactions on Arc. Essential for gas estimation, fee optimization, and time-sensitive transaction pricing.

Returns the current suggested priority fee (tip) per gas in wei on Arc. This is the amount paid directly to validators to incentivize faster transaction inclusion in EIP-1559 compatible blocks.

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

EIP-1559 Transaction Building - Get the recommended tip to include in maxPriorityFeePerGas when constructing type-2 transactions on Arc
Fee Optimization - Balance transaction speed against cost by adjusting the priority fee relative to the suggested value
Time-Sensitive Transactions - Increase the tip above the suggested value for DEX swaps, liquidations, or other latency-sensitive operations on crossborder settlement, merchant payments, institutional clearing, and USDC-denominated financial applications
Gas Price Estimation - Combine with baseFeePerGas from the latest block to calculate the total maxFeePerGas for accurate fee estimation

Code Examples

Common Use Cases

1. Build an EIP-1559 Transaction

Construct a properly priced type-2 transaction on Arc:

JavaScript

import { JsonRpcProvider, Wallet, parseEther } from 'ethers';

const provider = new JsonRpcProvider('https://api-arc-mainnet.n.dwellir.com/YOUR_API_KEY');

async function buildEIP1559Transaction(privateKey, to, valueEth) {
  const wallet = new Wallet(privateKey, provider);

  // Get current fee data
  const feeData = await provider.getFeeData();
  const latestBlock = await provider.getBlock('latest');
  const baseFee = latestBlock.baseFeePerGas;

  // Set maxPriorityFeePerGas from the suggestion
  const maxPriorityFeePerGas = feeData.maxPriorityFeePerGas;

  // maxFeePerGas = 2 * baseFee + maxPriorityFeePerGas (buffer for base fee increases)
  const maxFeePerGas = baseFee * 2n + maxPriorityFeePerGas;

  const tx = await wallet.sendTransaction({
    to,
    value: parseEther(valueEth),
    type: 2,
    maxPriorityFeePerGas,
    maxFeePerGas
  });

  console.log('Sent with priority fee:', Number(maxPriorityFeePerGas) / 1e9, 'Gwei');
  return tx;
}

2. Dynamic Fee Strategy

Adjust priority fees based on transaction urgency:

JavaScript

async function getFeeByUrgency(provider, urgency = 'standard') {
  const feeData = await provider.getFeeData();
  const basePriorityFee = feeData.maxPriorityFeePerGas;

  const multipliers = {
    low: 0.8,       // Willing to wait
    standard: 1.0,  // Normal speed
    fast: 1.5,      // Faster inclusion
    urgent: 2.0     // Next-block target
  };

  const multiplier = multipliers[urgency] || 1.0;
  const adjustedFee = BigInt(Math.ceil(Number(basePriorityFee) * multiplier));

  const block = await provider.getBlock('latest');
  const maxFeePerGas = block.baseFeePerGas * 2n + adjustedFee;

  return {
    maxPriorityFeePerGas: adjustedFee,
    maxFeePerGas
  };
}

// Usage
const fees = await getFeeByUrgency(provider, 'fast');
console.log('Priority fee:', Number(fees.maxPriorityFeePerGas) / 1e9, 'Gwei');
console.log('Max fee:', Number(fees.maxFeePerGas) / 1e9, 'Gwei');

3. Priority Fee Monitor

Track priority fee changes over time on Arc:

JavaScript

async function monitorPriorityFee(provider, interval = 12000) {
  let previousFee = null;

  setInterval(async () => {
    const feeData = await provider.getFeeData();
    const currentFee = feeData.maxPriorityFeePerGas;
    const feeGwei = Number(currentFee) / 1e9;

    if (previousFee !== null) {
      const change = Number(currentFee - previousFee) / Number(previousFee) * 100;
      const direction = change > 0 ? 'UP' : change < 0 ? 'DOWN' : 'STABLE';
      console.log(`Priority fee: ${feeGwei.toFixed(4)} Gwei (${direction} ${Math.abs(change).toFixed(1)}%)`);
    } else {
      console.log(`Priority fee: ${feeGwei.toFixed(4)} Gwei`);
    }

    previousFee = currentFee;
  }, interval);
}

Best Practices

Use eth_feeHistory with percentile rewards for a more accurate priority fee estimate than the node's suggestion alone
The suggested priority fee is the minimum for timely inclusion -- multiply by 1.5-2x for faster confirmation on congested networks
Fall back to eth_gasPrice if eth_maxPriorityFeePerGas returns method not found (-32601) on non-EIP-1559 nodes
For L2 chains, the priority fee is typically much lower than L1 -- never reuse L1 gas parameters on L2
Cache with a short TTL (12 seconds, one block time) since priority fees change with each block

Arc fee market

Arc denominates gas in USDC and replaces Ethereum's per-block EIP-1559 recalculation with an EWMA-smoothed base fee, so quotes move gradually rather than spiking with a single busy block.

Parameter	Value
Minimum base fee	20 Gwei (protocol floor)
Maximum base fee	20,000 Gwei
Base fee target	~$0.01 per transaction under normal load
Gas throughput	30M gas per block
Base fee destination	Paid to the block beneficiary, not burned

Two consequences matter when you use this value:

Always clamp to the floor. A quote below 20 Gwei is unusable. Transactions whose maxFeePerGas is under the floor are dropped by the mempool without an error receipt and never appear in a block.
The next block's base fee is published in advance. Arc writes it into the parent header's extra_data as an 8-byte big-endian value, so you can read the upcoming base fee straight from the block header instead of extrapolating.

Because fees are dollar-denominated, show users the USDC cost rather than raw Gwei. See Arc's gas and fees reference for the current parameter set.

Error Handling

Common errors and solutions:

Error Code	Description	Solution
-32601	Method not found	The node may not support EIP-1559 - fall back to `eth_gasPrice`
-32603	Internal error	Retry with exponential backoff
-32005	Rate limit exceeded	Implement rate limiting and caching client-side

JavaScript

async function getSafePriorityFee(provider, maxRetries = 3) {
  for (let i = 0; i < maxRetries; i++) {
    try {
      const feeData = await provider.getFeeData();
      if (feeData.maxPriorityFeePerGas !== null) {
        return feeData.maxPriorityFeePerGas;
      }
      // Fallback: derive from legacy gas price
      const gasPrice = await provider.send('eth_gasPrice', []);
      return BigInt(gasPrice);
    } catch (error) {
      if (error.code === -32601) {
        // EIP-1559 not supported - use legacy gas price
        const gasPrice = await provider.send('eth_gasPrice', []);
        return BigInt(gasPrice);
      }
      if (i === maxRetries - 1) throw error;
      await new Promise(r => setTimeout(r, Math.pow(2, i) * 1000));
    }
  }
}

eth_gasPrice - Get the legacy gas price
eth_feeHistory - Get historical fee data for trend analysis
eth_estimateGas - Estimate gas units required for a transaction
eth_getBlockByNumber - Get block details including baseFeePerGas

Returns the current suggested priority fee (tip) per gas in wei on Arc. This is the amount paid directly to validators to incentivize faster transaction inclusion in EIP-1559 compatible blocks.

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

EIP-1559 Transaction Building - Get the recommended tip to include in maxPriorityFeePerGas when constructing type-2 transactions on Arc
Fee Optimization - Balance transaction speed against cost by adjusting the priority fee relative to the suggested value
Time-Sensitive Transactions - Increase the tip above the suggested value for DEX swaps, liquidations, or other latency-sensitive operations on crossborder settlement, merchant payments, institutional clearing, and USDC-denominated financial applications
Gas Price Estimation - Combine with baseFeePerGas from the latest block to calculate the total maxFeePerGas for accurate fee estimation

Code Examples

Common Use Cases

1. Build an EIP-1559 Transaction

Construct a properly priced type-2 transaction on Arc:

JavaScript

import { JsonRpcProvider, Wallet, parseEther } from 'ethers';

const provider = new JsonRpcProvider('https://api-arc-mainnet.n.dwellir.com/YOUR_API_KEY');

async function buildEIP1559Transaction(privateKey, to, valueEth) {
  const wallet = new Wallet(privateKey, provider);

  // Get current fee data
  const feeData = await provider.getFeeData();
  const latestBlock = await provider.getBlock('latest');
  const baseFee = latestBlock.baseFeePerGas;

  // Set maxPriorityFeePerGas from the suggestion
  const maxPriorityFeePerGas = feeData.maxPriorityFeePerGas;

  // maxFeePerGas = 2 * baseFee + maxPriorityFeePerGas (buffer for base fee increases)
  const maxFeePerGas = baseFee * 2n + maxPriorityFeePerGas;

  const tx = await wallet.sendTransaction({
    to,
    value: parseEther(valueEth),
    type: 2,
    maxPriorityFeePerGas,
    maxFeePerGas
  });

  console.log('Sent with priority fee:', Number(maxPriorityFeePerGas) / 1e9, 'Gwei');
  return tx;
}

2. Dynamic Fee Strategy

Adjust priority fees based on transaction urgency:

JavaScript

async function getFeeByUrgency(provider, urgency = 'standard') {
  const feeData = await provider.getFeeData();
  const basePriorityFee = feeData.maxPriorityFeePerGas;

  const multipliers = {
    low: 0.8,       // Willing to wait
    standard: 1.0,  // Normal speed
    fast: 1.5,      // Faster inclusion
    urgent: 2.0     // Next-block target
  };

  const multiplier = multipliers[urgency] || 1.0;
  const adjustedFee = BigInt(Math.ceil(Number(basePriorityFee) * multiplier));

  const block = await provider.getBlock('latest');
  const maxFeePerGas = block.baseFeePerGas * 2n + adjustedFee;

  return {
    maxPriorityFeePerGas: adjustedFee,
    maxFeePerGas
  };
}

// Usage
const fees = await getFeeByUrgency(provider, 'fast');
console.log('Priority fee:', Number(fees.maxPriorityFeePerGas) / 1e9, 'Gwei');
console.log('Max fee:', Number(fees.maxFeePerGas) / 1e9, 'Gwei');

3. Priority Fee Monitor

Track priority fee changes over time on Arc:

JavaScript

async function monitorPriorityFee(provider, interval = 12000) {
  let previousFee = null;

  setInterval(async () => {
    const feeData = await provider.getFeeData();
    const currentFee = feeData.maxPriorityFeePerGas;
    const feeGwei = Number(currentFee) / 1e9;

    if (previousFee !== null) {
      const change = Number(currentFee - previousFee) / Number(previousFee) * 100;
      const direction = change > 0 ? 'UP' : change < 0 ? 'DOWN' : 'STABLE';
      console.log(`Priority fee: ${feeGwei.toFixed(4)} Gwei (${direction} ${Math.abs(change).toFixed(1)}%)`);
    } else {
      console.log(`Priority fee: ${feeGwei.toFixed(4)} Gwei`);
    }

    previousFee = currentFee;
  }, interval);
}

Best Practices

Use eth_feeHistory with percentile rewards for a more accurate priority fee estimate than the node's suggestion alone
The suggested priority fee is the minimum for timely inclusion -- multiply by 1.5-2x for faster confirmation on congested networks
Fall back to eth_gasPrice if eth_maxPriorityFeePerGas returns method not found (-32601) on non-EIP-1559 nodes
For L2 chains, the priority fee is typically much lower than L1 -- never reuse L1 gas parameters on L2
Cache with a short TTL (12 seconds, one block time) since priority fees change with each block

Arc fee market

Arc denominates gas in USDC and replaces Ethereum's per-block EIP-1559 recalculation with an EWMA-smoothed base fee, so quotes move gradually rather than spiking with a single busy block.

Parameter	Value
Minimum base fee	20 Gwei (protocol floor)
Maximum base fee	20,000 Gwei
Base fee target	~$0.01 per transaction under normal load
Gas throughput	30M gas per block
Base fee destination	Paid to the block beneficiary, not burned

Two consequences matter when you use this value:

Always clamp to the floor. A quote below 20 Gwei is unusable. Transactions whose maxFeePerGas is under the floor are dropped by the mempool without an error receipt and never appear in a block.
The next block's base fee is published in advance. Arc writes it into the parent header's extra_data as an 8-byte big-endian value, so you can read the upcoming base fee straight from the block header instead of extrapolating.

Because fees are dollar-denominated, show users the USDC cost rather than raw Gwei. See Arc's gas and fees reference for the current parameter set.

Error Handling

Common errors and solutions:

Error Code	Description	Solution
-32601	Method not found	The node may not support EIP-1559 - fall back to `eth_gasPrice`
-32603	Internal error	Retry with exponential backoff
-32005	Rate limit exceeded	Implement rate limiting and caching client-side

JavaScript

async function getSafePriorityFee(provider, maxRetries = 3) {
  for (let i = 0; i < maxRetries; i++) {
    try {
      const feeData = await provider.getFeeData();
      if (feeData.maxPriorityFeePerGas !== null) {
        return feeData.maxPriorityFeePerGas;
      }
      // Fallback: derive from legacy gas price
      const gasPrice = await provider.send('eth_gasPrice', []);
      return BigInt(gasPrice);
    } catch (error) {
      if (error.code === -32601) {
        // EIP-1559 not supported - use legacy gas price
        const gasPrice = await provider.send('eth_gasPrice', []);
        return BigInt(gasPrice);
      }
      if (i === maxRetries - 1) throw error;
      await new Promise(r => setTimeout(r, Math.pow(2, i) * 1000));
    }
  }
}

eth_gasPrice - Get the legacy gas price
eth_feeHistory - Get historical fee data for trend analysis
eth_estimateGas - Estimate gas units required for a transaction
eth_getBlockByNumber - Get block details including baseFeePerGas

eth_maxPriorityFeePerGas - Arc RPC Method

When to Use This Method

Code Examples

Common Use Cases

1. Build an EIP-1559 Transaction

2. Dynamic Fee Strategy

3. Priority Fee Monitor

Best Practices

Arc fee market

Error Handling

On this page

eth_maxPriorityFeePerGas - Arc RPC Method

When to Use This Method

Code Examples

Common Use Cases

1. Build an EIP-1559 Transaction

2. Dynamic Fee Strategy

3. Priority Fee Monitor

Best Practices

Arc fee market

Error Handling

On this page