> ## Documentation Index
> Fetch the complete documentation index at: https://daehan-base.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# eth_feeHistory

> Returns historical base fees and priority fee percentiles for a range of blocks.

Returns historical gas information for a range of blocks, including base fees and the distribution of priority fees. Useful for building fee estimation strategies.

## Parameters

<ParamField body="blockCount" type="string | number" required>
  Number of blocks to return. Can be a decimal or hexadecimal integer. Maximum is typically 1024.
</ParamField>

<ParamField body="newestBlock" type="string" required>
  The highest block to include, as a block number in hex or a block tag (`"latest"`, `"pending"`, etc.).
</ParamField>

<ParamField body="rewardPercentiles" type="array" required>
  Array of percentile values (0–100) to sample from each block's priority fees. Example: `[25, 50, 75]` returns the 25th, 50th, and 75th percentile priority fees.
</ParamField>

## Returns

<ResponseField name="result" type="object">
  <Expandable title="Fee history fields">
    <ResponseField name="oldestBlock" type="string">The oldest block number in the result set (hex).</ResponseField>
    <ResponseField name="baseFeePerGas" type="array">Array of base fees per gas for each block, plus one extra for the next pending block.</ResponseField>
    <ResponseField name="gasUsedRatio" type="array">Array of gas used / gas limit ratios for each block (0.0 to 1.0).</ResponseField>
    <ResponseField name="reward" type="array">2D array of priority fee percentiles per block, matching the requested percentile values.</ResponseField>
  </Expandable>
</ResponseField>

## Example

<CodeGroup>
  ```json Request theme={null}
  {
    "jsonrpc": "2.0",
    "method": "eth_feeHistory",
    "params": ["0xa", "latest", [25, 50, 75]],
    "id": 1
  }
  ```

  ```json Response theme={null}
  {
    "jsonrpc": "2.0",
    "id": 1,
    "result": {
      "oldestBlock": "0x158a0e0",
      "baseFeePerGas": ["0xf5", "0xf7", "0xfa", "0xfc", "0xf8", "0xf5", "0xf2", "0xf0", "0xef", "0xf1", "0xf3"],
      "gasUsedRatio": [0.45, 0.62, 0.38, 0.71, 0.55, 0.49, 0.43, 0.37, 0.52, 0.64],
      "reward": [
        ["0x1", "0x1", "0x2"],
        ["0x1", "0x1", "0x1"]
      ]
    }
  }
  ```
</CodeGroup>