# getbestblockhash

> For the complete documentation index, see [llms.txt](/docs/llms.txt).

POST https://bitcoin-mainnet.g.alchemy.com/v2/{apiKey}

Returns the hash of the most-work fully-validated tip block in the active Bitcoin blockchain.


Reference: https://www.alchemy.com/docs/chains/bitcoin/bitcoin-api-endpoints/getbestblockhash

## Result

**result** (string): The hash of the best block in the longest chain.

## Example

### Response

```json
{
  "jsonrpc": "2.0",
  "result": "00000000000000000001fe9b58c5ccd401de62139c29e7dbfd32bd3cf14b650c",
  "id": 1
}
```

## Code Examples

### cURL

```bash
curl --request POST \
  --url https://bitcoin-mainnet.g.alchemy.com/v2/docs-demo \
  --header 'Content-Type: application/json' \
  --data '{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "getbestblockhash"
}'
```

### JavaScript

```javascript
const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({jsonrpc: '2.0', id: 1, method: 'getbestblockhash'})
};

fetch('https://bitcoin-mainnet.g.alchemy.com/v2/docs-demo', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));
```

### Python

```python
import requests

url = "https://bitcoin-mainnet.g.alchemy.com/v2/docs-demo"

payload = {
    "jsonrpc": "2.0",
    "id": 1,
    "method": "getbestblockhash"
}
headers = {"Content-Type": "application/json"}

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

print(response.text)
```

### Go

```go
package main

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

func main() {

	url := "https://bitcoin-mainnet.g.alchemy.com/v2/docs-demo"

	payload := strings.NewReader("{\n  \"jsonrpc\": \"2.0\",\n  \"id\": 1,\n  \"method\": \"getbestblockhash\"\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))

}
```

### Java

```java
HttpResponse<String> response = Unirest.post("https://bitcoin-mainnet.g.alchemy.com/v2/docs-demo")
  .header("Content-Type", "application/json")
  .body("{\n  \"jsonrpc\": \"2.0\",\n  \"id\": 1,\n  \"method\": \"getbestblockhash\"\n}")
  .asString();
```

### C#

```csharp
using RestSharp;


var options = new RestClientOptions("https://bitcoin-mainnet.g.alchemy.com/v2/docs-demo");
var client = new RestClient(options);
var request = new RestRequest("");
request.AddJsonBody("{\n  \"jsonrpc\": \"2.0\",\n  \"id\": 1,\n  \"method\": \"getbestblockhash\"\n}", false);
var response = await client.PostAsync(request);

Console.WriteLine("{0}", response.Content);

```


## OpenRPC Method Specification

```yaml
name: getbestblockhash
summary: Get the best (tip) block hash of the longest valid chain
description: |
  Returns the hash of the most-work fully-validated tip block in the active Bitcoin blockchain.
params: []
result:
  name: result
  description: The hash of the best block in the longest chain.
  schema:
    title: Bitcoin Block Hash
    type: string
    pattern: ^[a-fA-F0-9]{64}$
    description: A 64-character hex string representing the block hash.
examples:
  - name: getbestblockhash example
    params: []
    result:
      name: result
      value: 00000000000000000001fe9b58c5ccd401de62139c29e7dbfd32bd3cf14b650c
```