eth_blobBaseFee - Ethereum

Example code for the eth_blobBaseFee JSON RPC method. Сomplete guide on how to use eth_blobBaseFee JSON RPC in GetBlock Web3 documentation.

This method returns the current blob base fee in wei, hex-encoded. Introduced with EIP-4844 (Dencun, March 2024), blob transactions carry their data-availability payload separately from calldata and are priced independently via blobGasPrice. Post-Fusaka (December 2025) and its BPO forks, blob capacity is 14 target / 21 max blobs per block. Rollups and any application posting blob-carrying transactions read this to price their data-availability spend.

Parameters

This method takes no parameters.

Request

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "eth_blobBaseFee",
    "params": [],
    "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_blobBaseFee',
    params: [],
    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_blobBaseFee',
        'params': [],
        '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_blobBaseFee",
            "params": [],
            "id": "getblock.io"
        }))
        .send()
        .await?
        .json::<Value>()
        .await?;
    
    println!("Result: {}", response["result"]);
    Ok(())
}

Response

{
    "jsonrpc": "2.0",
    "result": "0x7ad94d",
    "id": "getblock.io"
}

Response Parameters

Parameter	Type	Description
jsonrpc	string	JSON-RPC protocol version ("2.0")
id	string	Request identifier matching the request
result	string	Hex-encoded blob base fee in wei per blob gas unit

Use Cases

• L2 Rollup Cost Modeling: L2 sequencers price blob-posting cost before submitting compressed batches to L1

• Blob Congestion Detection: Track the blob base fee to detect L2 batch-posting congestion or blob market spikes

• Blob Transaction Pricing: Applications posting EIP-4844 blob transactions compute maxFeePerBlobGas bids based on this floor

• Data Availability Analytics: Research and dashboards tracking DA spend across the rollup ecosystem

Error Handling

Error Code	Message	Description
-32603	Internal error	Node's blob fee tracker failed to produce a result

Web3 Integration

Ethers.js

ethers-example.js

import { ethers } from 'ethers';

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

const blobBaseFeeHex = await provider.send('eth_blobBaseFee', []);
const blobBaseFee = BigInt(blobBaseFeeHex);
console.log('Blob base fee (wei):', blobBaseFee.toString());

Viem

viem-example.js

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

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

const blobBaseFee = await client.getBlobBaseFee();
console.log('Blob base fee (wei):', blobBaseFee);