# getbestblockhash - Bitcoin

This method returns the hash of the best (tip) block in the most-work, fully validated chain.

### Parameters

* none

### Request

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

```bash
curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "getbestblockhash",
    "params": [],
    "id": "getblock.io"
}'
```

{% endtab %}

{% tab title="Axios" %}

```javascript
import axios from 'axios';

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

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

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

{% endtab %}

{% tab title="Request" %}

```python
import requests
import json

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

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

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

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

{% endtab %}

{% tab title="Rust" %}

```rust
use reqwest::header;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = reqwest::Client::new();
    
    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header(header::CONTENT_TYPE, "application/json")
        .body(r#"{
            "jsonrpc": "2.0",
            "method": "getbestblockhash",
            "params": [],
            "id": "getblock.io"
        }"#)
        .send()
        .await?;
    
    println!("{}", response.text().await?);
    Ok(())
}
```

{% endtab %}
{% endtabs %}

### Response

```json
{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "000000000000000000046b9302e08c16ea186950f42a5498320ddd1bd7ab3428"
}
```

### Response Parameters

| Field  | Type   | Description                                          |
| ------ | ------ | ---------------------------------------------------- |
| result | string | The block hash hex string of the current best block. |

### Use Case

The `getbestblockhash` method is essential for:

* Monitoring blockchain tip for new blocks
* Synchronizing with the latest chain state
* Building block explorers and dashboards
* Implementing chain reorganization detection
* Creating real-time blockchain monitoring tools
* Supporting payment confirmation tracking

### Error Handling

| Status Code | Error Message | Cause                            |
| ----------- | ------------- | -------------------------------- |
| 403         | Forbidden     | Missing or invalid ACCESS-TOKEN. |

### Integration Notes

The `getbestblockhash` method helps developers:

* Track the current chain tip
* Build real-time block notification systems
* Implement chain synchronization logic
* Create blockchain monitoring dashboards
* Support transaction confirmation tracking


---

# 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/bitcoin-btc/btc_getbestblockhash.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.
