web3_sha3

curl --request POST \
  --url https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300 \
  --header 'Content-Type: application/json' \
  --data '
{
  "jsonrpc": "2.0",
  "method": "web3_sha3",
  "id": 1,
  "params": [
    "0x436861696E737461636B"
  ]
}
'

import requests

url = "https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300"

payload = {
    "jsonrpc": "2.0",
    "method": "web3_sha3",
    "id": 1,
    "params": ["0x436861696E737461636B"]
}
headers = {"Content-Type": "application/json"}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({jsonrpc: '2.0', method: 'web3_sha3', id: 1, params: ['0x436861696E737461636B']})
};

fetch('https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'jsonrpc' => '2.0',
    'method' => 'web3_sha3',
    'id' => 1,
    'params' => [
        '0x436861696E737461636B'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300"

	payload := strings.NewReader("{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"web3_sha3\",\n  \"id\": 1,\n  \"params\": [\n    \"0x436861696E737461636B\"\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300")
  .header("Content-Type", "application/json")
  .body("{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"web3_sha3\",\n  \"id\": 1,\n  \"params\": [\n    \"0x436861696E737461636B\"\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"web3_sha3\",\n  \"id\": 1,\n  \"params\": [\n    \"0x436861696E737461636B\"\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "jsonrpc": "<string>",
  "id": 123,
  "result": "<string>"
}

POST

efb0a5eccd2caa5135eb54eba6f7f300

web3_sha3

curl --request POST \
  --url https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300 \
  --header 'Content-Type: application/json' \
  --data '
{
  "jsonrpc": "2.0",
  "method": "web3_sha3",
  "id": 1,
  "params": [
    "0x436861696E737461636B"
  ]
}
'

import requests

url = "https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300"

payload = {
    "jsonrpc": "2.0",
    "method": "web3_sha3",
    "id": 1,
    "params": ["0x436861696E737461636B"]
}
headers = {"Content-Type": "application/json"}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({jsonrpc: '2.0', method: 'web3_sha3', id: 1, params: ['0x436861696E737461636B']})
};

fetch('https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'jsonrpc' => '2.0',
    'method' => 'web3_sha3',
    'id' => 1,
    'params' => [
        '0x436861696E737461636B'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300"

	payload := strings.NewReader("{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"web3_sha3\",\n  \"id\": 1,\n  \"params\": [\n    \"0x436861696E737461636B\"\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300")
  .header("Content-Type", "application/json")
  .body("{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"web3_sha3\",\n  \"id\": 1,\n  \"params\": [\n    \"0x436861696E737461636B\"\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://optimism-mainnet.core.chainstack.com/efb0a5eccd2caa5135eb54eba6f7f300")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"web3_sha3\",\n  \"id\": 1,\n  \"params\": [\n    \"0x436861696E737461636B\"\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "jsonrpc": "<string>",
  "id": 123,
  "result": "<string>"
}

Optimism API method web3_sha3 computes the Keccak-256 hash of the given data. This method is a utility function often used in Optimism for generating hashes of arbitrary data, which is a common requirement for various cryptographic operations. This example computes Keccak-256 for the value Chainstack. Chainstack in hex: 0x436861696E737461636B.

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Parameters

data — the data to hash, typically provided as a hexadecimal string.

Response

result — the Keccak-256 hash of the input data, returned as a hexadecimal string.

Use case

The web3_sha3 method is essential for:

Generating identifiers or hashes for on-chain data storage or referencing.
Creating cryptographic proofs that require a hash of data.
Developers needing to perform off-chain hash calculations that match the Optimism network’s hashing algorithm.

Body

application/json

jsonrpc

string

default:2.0

required

method

string

default:web3_sha3

required

integer

default:1

required

params

string[]

required

Response

200 - application/json

The SHA3 result of the given data

jsonrpc

string

integer

result

string

The Keccak-256 hash of the input data.

Last modified on June 22, 2026

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web3_sha3 | Optimism

Parameters

Response

Use case

Body

Response

​Parameters

​Response

​Use case

Body

Response

Parameters

Response

Use case