# getblockheader

If verbose is false, returns a string that is serialized, hex-encoded data for blockheader ‘hash’.

If verbose is true, returns an Object with information about blockheader ‘hash’.

### Argument #1 - blockhash

**Type:** string, required

The block hash

### Argument #2 - verbose

**Type:** boolean, optional, default=true

true for a json object, false for the hex-encoded data

### Result (for verbose = true)

```
{                                 (json object)
  "hash" : "hex",                 (string) the block hash (same as provided)
  "confirmations" : n,            (numeric) The number of confirmations, or -1 if the block is not on the main chain
  "height" : n,                   (numeric) The block height or index
  "version" : n,                  (numeric) The block version
  "versionHex" : "hex",           (string) The block version formatted in hexadecimal
  "merkleroot" : "hex",           (string) The merkle root
  "time" : xxx,                   (numeric) The block time expressed in UNIX epoch time
  "mediantime" : xxx,             (numeric) The median block time expressed in UNIX epoch time
  "nonce" : n,                    (numeric) The nonce
  "bits" : "hex",                 (string) The bits
  "difficulty" : n,               (numeric) The difficulty
  "chainwork" : "hex",            (string) Expected number of hashes required to produce the current chain
  "nTx" : n,                      (numeric) The number of transactions in the block
  "previousblockhash" : "hex",    (string) The hash of the previous block
  "nextblockhash" : "hex"         (string) The hash of the next block
}
```

### Result (for verbose=false)

| Name | Type   | Description                                                    |
| ---- | ------ | -------------------------------------------------------------- |
| hex  | string | A string that is serialized, hex-encoded data for block ‘hash’ |

**Request**

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

```bash
curl --location --request POST 'https://btc.api.watchdata.io/node/jsonrpc?api_key=your_api_key' \
--header 'x-api-key: your_api_key' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "1.0",
    "id": "curltest",
    "method": "getblockheader",
    "params": [
        "00000000c937983704a73af28acdec37b049d214adbda81d7e2a3dd146f6ed09"
    ]
}'
```

{% endtab %}

{% tab title="Postman" %}

```json
URL: https://btc.api.watchdata.io/node/jsonrpc?api_key=your_api_key
RequestType: POST
Body: 
{
    "jsonrpc": "1.0",
    "id": "curltest",
    "method": "getblockheader",
    "params": [
        "00000000c937983704a73af28acdec37b049d214adbda81d7e2a3dd146f6ed09"
    ]
}
```

{% endtab %}
{% endtabs %}

**Response**

```json
{
    "hash": "00000000c937983704a73af28acdec37b049d214adbda81d7e2a3dd146f6ed09",
    "confirmations": 735634,
    "height": 1000,
    "version": 1,
    "versionHex": "00000001",
    "merkleroot": "fe28050b93faea61fa88c4c630f0e1f0a1c24d0082dd0e10d369e13212128f33",
    "time": 1232346882,
    "mediantime": 1232344831,
    "nonce": 2595206198,
    "bits": "1d00ffff",
    "difficulty": 1,
    "chainwork": "000000000000000000000000000000000000000000000000000003e903e903e9",
    "nTx": 1,
    "previousblockhash": "0000000008e647742775a230787d66fdf92c46a48c896bfbc85cdc8acc67e87d",
    "nextblockhash": "00000000a2887344f8db859e372e7e4bc26b23b9de340f725afbf2edb265b4c6"
}
```


---

# 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.watchdata.io/blockchain-apis/bitcoin-api/blockchain-rpcs/getblockheader.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.