web3_sha3 - Robinhood

Example code for the web3_sha3 JSON-RPC method. Complete guide to using the web3_sha3 JSON-RPC method in GetBlock.io Web3 documentation.

Returns the Keccak-256 hash of the given data. Despite the method name sha3, this returns Keccak-256 (the pre-standardization variant), not the standardized SHA3-256 — same as Ethereum.

Parameters

Parameter	Type	Required	Description
data	string	Yes	Hex-encoded data to hash (0x... prefix required)

Request Example

cURL

curl --location --request POST 'https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "web3_sha3",
    "params": [
        "0x68656c6c6f20776f726c64"
    ],
    "id": "getblock.io"
}'

JavaScript (Axios)

import axios from 'axios';

const data = JSON.stringify({
    "jsonrpc": "2.0",
    "method": "web3_sha3",
    "params": [
        "0x68656c6c6f20776f726c64"
    ],
    "id": "getblock.io"
});

const config = {
    method: 'post',
    url: 'https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/',
    headers: {
        'Content-Type': 'application/json'
    },
    data: data
};

axios(config)
    .then(response => console.log(JSON.stringify(response.data, null, 2)))
    .catch(error => console.log(error));

Python (Requests)

import requests
import json

url = "https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/"

payload = json.dumps({
    "jsonrpc": "2.0",
    "method": "web3_sha3",
    "params": [
        "0x68656c6c6f20776f726c64"
    ],
    "id": "getblock.io"
})

headers = {
    'Content-Type': 'application/json'
}

response = requests.post(url, headers=headers, data=payload)
print(response.text)

Rust (Reqwest)

use reqwest::Client;
use serde_json::json;

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

    let payload = json!({
        "jsonrpc": "2.0",
        "method": "web3_sha3",
        "params": [
                "0x68656c6c6f20776f726c64"
        ],
        "id": "getblock.io"
});

    let response = client
        .post("https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&payload)
        .send()
        .await?;

    let result: serde_json::Value = response.json().await?;
    println!("{:#?}", result);

    Ok(())
}

Response Example

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "0x47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad"
}

Response Parameters

Field	Type	Description
result	DATA (32 bytes)	Keccak-256 hash of the input data

Use Cases

• Computing function selectors for contract calls (first 4 bytes of keccak256("functionName(types)"))

• Computing storage slot positions for mappings and arrays

• Computing event topic hashes for Stock Token Transfer events

Error Handling

Status Code	Error Message	Cause
403	Forbidden	Missing or invalid <ACCESS-TOKEN>
-32602	Invalid params	Request parameters are missing or malformed
-32603	Internal error	Server-side error while processing the request
429	Too Many Requests	Rate limit exceeded for your plan

SDK Integration

ethers.js

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider('https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/');

// Generic JSON-RPC call (works for any method):
const result = await provider.send('web3_sha3', ["0x68656c6c6f20776f726c64"]);
console.log(result);

// Many standard methods have typed wrappers on ethers Provider,
// e.g. provider.getBalance(addr), provider.getBlock(n), provider.getTransaction(hash).

viem

import { createPublicClient, http } from 'viem';

const client = createPublicClient({
    transport: http('https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/')
});

// Generic JSON-RPC request (works for any method):
const result = await client.request({
    method: 'web3_sha3',
    params: ["0x68656c6c6f20776f726c64"]
});
console.log(result);

// Many standard methods have typed wrappers on PublicClient,
// e.g. client.getBalance({ address }), client.getBlock({ blockNumber }).