eth_feeHistory - Sonic

Example code for the eth_feeHistory JSON-RPC method. Complete guide on how to use eth_feeHistory JSON-RPC in GetBlock Web3 documentation.

This method returns historical base fees and priority-fee percentiles over a range of blocks. It is used to model fees for EIP-1559 transactions.

Parameters

Parameter	Type	Required	Description
blockCount	string	Yes	Number of blocks in the range, hex-encoded
newestBlock	string	Yes	Highest block of the range, hex or "latest"
rewardPercentiles	array	No	Percentiles to sample priority fees at

Request

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "eth_feeHistory",
    "params": ["0x5", "latest", [25, 50, 75]],
    "id": "getblock.io"
}'

Axios

example.js

const axios = require('axios');

const response = await axios.post('https://go.getblock.io/<ACCESS-TOKEN>/', {
    jsonrpc: '2.0',
    method: 'eth_feeHistory',
    params: ["0x5", "latest", [25, 50, 75]],
    id: 'getblock.io'
}, {
    headers: { 'Content-Type': 'application/json' }
});

console.log(response.data.result);

Request

example.py

import requests

response = requests.post(
    'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers={'Content-Type': 'application/json'},
    json={
        'jsonrpc': '2.0',
        'method': 'eth_feeHistory',
        'params': ["0x5", "latest", [25, 50, 75]],
        'id': 'getblock.io'
    }
)

print(response.json())

Rust

example.rs

use reqwest::Client;
use serde_json::{json, Value};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&json!({
            "jsonrpc": "2.0",
            "method": "eth_feeHistory",
            "params": ["0x5", "latest", [25, 50, 75]],
            "id": "getblock.io"
        }))
        .send()
        .await?
        .json::<Value>()
        .await?;

    println!("Result: {}", response["result"]);
    Ok(())
}

Response

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": {
        "oldestBlock": "0x1e847b",
        "baseFeePerGas": [
            "0x3b9aca00",
            "0x3b9aca00",
            "0x3b9aca00",
            "0x3b9aca00",
            "0x3b9aca00",
            "0x3b9aca00"
        ],
        "gasUsedRatio": [
            0.42,
            0.51,
            0.38,
            0.6,
            0.47
        ],
        "reward": [
            [
                "0x3b9aca00",
                "0x3b9aca00",
                "0x77359400"
            ]
        ]
    }
}

Response Parameters

Parameter	Type	Description
jsonrpc	string	JSON-RPC protocol version ("2.0")
id	string	Request identifier matching the request
result	object	Fee history object over the requested block range

Result Object

Field	Type	Description
oldestBlock	string	Lowest block of the returned range, hex-encoded
baseFeePerGas	array	Base fee per gas for each block, including the next
gasUsedRatio	array	Ratio of gas used to gas limit per block
reward	array	Priority-fee samples per block at the requested percentiles

Use Cases

• Fee Modeling: Model base-fee trends for EIP-1559 pricing

• Tip Estimation: Derive priority-fee tiers from historical percentiles

• Congestion Analysis: Read gas-used ratios to gauge network load

• Wallet Fee UX: Build fast, normal, and slow fee options

Error Handling

Error Code	Message	Description
-32602	Invalid params	A parameter is missing or has the wrong type or format
-32603	Internal error	The node failed to process the request

Web3 Integration

Ethers.js

ethers-example.js

const { ethers } = require('ethers');

const provider = new ethers.JsonRpcProvider('https://go.getblock.io/<ACCESS-TOKEN>/');

const history = await provider.send('eth_feeHistory', ['0x5', 'latest', [25, 50, 75]]);
console.log(history);

Viem

viem-example.js

import { createPublicClient, http } from 'viem';
import { sonic } from 'viem/chains';

const client = createPublicClient({ chain: sonic, transport: http('https://go.getblock.io/<ACCESS-TOKEN>/') });

const history = await client.getFeeHistory({ blockCount: 5, rewardPercentiles: [25, 50, 75] });
console.log(history);