# web3\_sha3 - Celo

This method the Keccak-256 hash of the given data on Celo. This is useful for hashing data for signatures, event topic generation, and other cryptographic operations.

## Parameters

| Parameter | Type   | Required | Description                |
| --------- | ------ | -------- | -------------------------- |
| data      | string | Yes      | Data to hash (hex encoded) |

## Request Example

{% tabs %}
{% tab title="cURL" %}
{% code title="curl" %}

```bash
curl -X POST https://go.getblock.io/<ACCESS-TOKEN>/ \
-H "Content-Type: application/json" \
-d '{
  "jsonrpc": "2.0",
  "id": "getblock.io",
  "method": "web3_sha3",
  "params": ["0x68656c6c6f"]
}'
```

{% endcode %}
{% endtab %}

{% tab title="JavaScript (Axios)" %}
{% code title="request.js" %}

```javascript
const axios = require('axios');

const url = 'https://go.getblock.io/<ACCESS-TOKEN>/';

const payload = {
  jsonrpc: '2.0',
  id: 'getblock.io',
  method: 'web3_sha3',
  params: ['0x68656c6c6f'] // "hello" in hex
};

axios.post(url, payload, {
  headers: { 'Content-Type': 'application/json' }
})
.then(response => console.log(response.data))
.catch(error => console.error(error));
```

{% endcode %}
{% endtab %}

{% tab title="Python" %}
{% code title="request.py" %}

```python
import requests
import json

url = "https://go.getblock.io/<ACCESS-TOKEN>/"

payload = {
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "method": "web3_sha3",
    "params": ["0x68656c6c6f"]
}

response = requests.post(url, headers={"Content-Type": "application/json"}, json=payload)
print(response.json())
```

{% endcode %}
{% endtab %}
{% endtabs %}

## Response Example

{% code title="response.json" %}

```json
{
  "jsonrpc": "2.0",
  "id": "getblock.io",
  "result": "0x1c8aff950685c2ed4bc3174f3472287b56d9517b9c948127319a09a7a36deac8"
}
```

{% endcode %}

## Response Definition

| Field  | Type   | Description     |
| ------ | ------ | --------------- |
| result | string | Keccak-256 hash |

## Use Cases

* Generate event signatures
* Hash data for verification
* Create function selectors
* Cryptographic operations

## Error Handling

| Error Code | Description    |
| ---------- | -------------- |
| -32602     | Invalid params |
| -32603     | Internal error |

## SDK Integration

{% tabs %}
{% tab title="Ethers.js" %}
{% code title="ethers.js" %}

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

const hash = ethers.keccak256(ethers.toUtf8Bytes('hello'));
console.log(hash);
```

{% endcode %}
{% endtab %}
{% endtabs %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.getblock.io/api-reference/celo/web3_sha3-celo.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.