eth_feeHistory

Returns historical gas information for the Unichain network. This method is useful for gas price estimation and understanding network congestion patterns over time.

Parameters

1. QUANTITY - Number of blocks to retrieve. Must be between 1 and 1024.
2. QUANTITY|TAG - Highest block number to retrieve from (or "latest", "earliest", "pending").
3. Array - Array of percentile values (0-100) to retrieve priority fees for.

Returns

Object containing:

• oldestBlock: QUANTITY - Lowest block number returned
• baseFeePerGas: Array - Array of base fees per gas for each block
• gasUsedRatio: Array - Array of gas used ratios for each block (0.0 to 1.0)
• reward: Array - Array of arrays containing priority fees at requested percentiles

Implementation Example

cURL

curl -X POST https://api-unichain-mainnet.n.dwellir.com/YOUR_API_KEY \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_feeHistory",
    "params": ["0x4", "latest", [25, 50, 75]],
    "id": 1
  }'

JavaScript

const response = await fetch('https://api-unichain-mainnet.n.dwellir.com/YOUR_API_KEY', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    jsonrpc: '2.0',
    method: 'eth_feeHistory',
    params: ['0x4', 'latest', [25, 50, 75]],
    id: 1
  })
});

const data = await response.json();
console.log(data.result);

Response Example

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "oldestBlock": "0x1a2b3c4",
    "baseFeePerGas": [
      "0x3b9aca00",
      "0x3b9aca00",
      "0x3b9aca00",
      "0x3b9aca00"
    ],
    "gasUsedRatio": [0.5, 0.6, 0.4, 0.7],
    "reward": [
      ["0x77359400", "0x77359400", "0x77359400"],
      ["0x77359400", "0x77359400", "0x77359400"],
      ["0x77359400", "0x77359400", "0x77359400"]
    ]
  }
}

This example shows fee history for 4 blocks with priority fee percentiles at 25%, 50%, and 75%.

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Need help? Contact our support team or check the Unichain documentation.