# Bitcoin (BTC)

### Overview

Bitcoin is the first and largest decentralized cryptocurrency network, launched in 2009 by the pseudonymous Satoshi Nakamoto. It operates as a peer-to-peer electronic cash system, enabling trustless value transfer without intermediaries.

#### Key Features

* **Decentralized Network**: Secured by thousands of nodes worldwide with no central authority
* **Proof of Work Consensus**: Mining-based security with SHA-256 hashing algorithm
* **21 Million Supply Cap**: Fixed maximum supply creating digital scarcity
* **10-Minute Block Time**: Average block confirmation every 10 minutes
* **SegWit & Taproot**: Modern protocol upgrades for scalability and privacy
* **PSBT Support**: Partially Signed Bitcoin Transactions for secure multi-party signing
* **Lightning Network Compatible**: Layer 2 scaling solution support

## Quickstart

In this section, you will learn how to make your first call with either:

* Axios
* Python

### Quickstart with Axios

Before you begin, you must have already installed `npm` or `yarn` on your local machine. If not, check out [npm](https://docs.npmjs.com/downloading-and-installing-node-js-and-npm) or [yarn](https://classic.yarnpkg.com/lang/en/docs/install).

1. Set up your project using this command:

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

```bash
mkdir bitcoin-api-quickstart
cd bitcoin-api-quickstart
npm init --yes
```

{% endtab %}

{% tab title="Yarn" %}

```bash
mkdir bitcoin-api-quickstart
cd bitcoin-api-quickstart
yarn init --yes
```

{% endtab %}
{% endtabs %}

{% hint style="info" %}
This creates a project directory named `bitcoin-api-quickstart` and initialises a Node.js project within it.
{% endhint %}

2. Install Axios using this command:\
   Using npm:

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

```bash
npm install axios
```

{% endtab %}

{% tab title="yarn" %}

```bash
yarn add axios
```

{% endtab %}
{% endtabs %}

3. Create a new file and name it `index.js`. This is where you will make your first call.
4. Set the ES module `"type": "module"` in your `package.json`.
5. Add the following code to the file (`index.js`):

   ```js
   import axios from 'axios'
   let data = JSON.stringify({
       "jsonrpc": "2.0",
       "method": "analyzepsbt",
       "params": [
           "cHNidP8BAEICAAAAATJIj43goxJCsLjdKM5Uly44S8Vp6cim1VW89Rx5fFPpAAAAAAD/////AQAAAAAAAAAABmoEAAECAwAAAAAAAAA="
       ],
       "id": "getblock.io"
   });

   let config = {
     method: "post",
     maxBodyLength: Infinity,
     url: "https://go.getblock.io/<ACCESS_TOKEN>",
     headers: {
       "Content-Type": "application/json",
     },
     data: data,
   };

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

   ```

   > Replace `<ACCESS_TOKEN>` with your actual access token from GetBlock.
6. Run the script:

   ```bash
   node index.js
   ```

   The sequence number and authentication key log in your console like this:

   ```json
   {
       "jsonrpc": "2.0",
       "result": {
           "inputs": [
               {
                   "has_utxo": false,
                   "is_final": false,
                   "next": "updater"
               }
           ],
           "next": "updater"
       },
       "id": "getblock.io"
   }
   ```

### Quickstart with Python and Requests

Before you begin, you must have installed Python and Pip on your local machine.

1. Set up your project using this command:

   ```bash
   mkdir bitcoin-api-quickstart
   cd bitcoin-api-quickstart
   ```
2. Set up a virtual environment to isolate dependencies:

   ```bash
   python -m venv venv

   # On Windows, use venv\Scripts\activate
   ```
3. Install the requests library:

   ```bash
   pip install requests
   ```
4. Create a new file called [`main.py`](http://main.py) and insert the following code:

   ```python
   import requests
   import json

   url = "https://go.getblock.io/<ACCESS_TOKEN>"

   payload = json.dumps({
       "jsonrpc": "2.0",
       "method": "analyzepsbt",
       "params": [
           "cHNidP8BAEICAAAAATJIj43goxJCsLjdKM5Uly44S8Vp6cim1VW89Rx5fFPpAAAAAAD/////AQAAAAAAAAAABmoEAAECAwAAAAAAAAA="
       ],
       "id": "getblock.io"
   })
   headers = {
     'Content-Type': 'application/json'
   }

   response = requests.request("POST", url, headers=headers, data=payload)

   print(response.text)

   ```

   > Replace `<ACCESS_TOKEN>` with your actual access token from GetBlock.
5. Run the script:

   ```bash
   python main.py
   ```

### Base URL

{% tabs %}
{% tab title="Franfurt, Germany" %}

```bash
https://go.getblock.io
```

{% endtab %}
{% endtabs %}

### Supported Network

* Mainnet
* Testnet

### Available API Methods

GetBlock provides access to 45 Bitcoin RPC endpoints organized into the following categories:

#### PSBT & Transaction Building (13 methods)

Methods for creating, analyzing, and finalizing Partially Signed Bitcoin Transactions.

| Method                | Description                                         |
| --------------------- | --------------------------------------------------- |
| analyzepsbt           | Analyzes and provides information about a PSBT      |
| combinepsbt           | Combines multiple PSBTs into one                    |
| combinerawtransaction | Combines multiple partially signed raw transactions |
| converttopsbt         | Converts a raw transaction to PSBT format           |
| createpsbt            | Creates a new PSBT with given inputs and outputs    |
| createrawtransaction  | Creates a raw transaction                           |
| decodepsbt            | Decodes a PSBT to JSON                              |
| decoderawtransaction  | Decodes a raw transaction to JSON                   |
| decodescript          | Decodes a hex-encoded script                        |
| finalizepsbt          | Finalizes a PSBT for broadcast                      |
| fundrawtransaction    | Adds inputs to a raw transaction                    |
| joinpsbts             | Joins multiple PSBTs with different inputs          |
| utxoupdatepsbt        | Updates PSBT with UTXO data                         |

#### Blockchain & Block Information (13 methods)

Methods for querying blockchain state and block data.

| Method                | Description                             |
| --------------------- | --------------------------------------- |
| getbestblockhash      | Returns the hash of the best block      |
| getblock              | Returns block data for a given hash     |
| getblockchaininfo     | Returns blockchain state information    |
| getblockcount         | Returns the current block height        |
| getblockfilter        | Returns BIP 157 block filter            |
| getblockhash          | Returns block hash at given height      |
| getblockheader        | Returns block header information        |
| getblockstats         | Returns per-block statistics            |
| getblocktemplate      | Returns data for mining a block         |
| getchaintips          | Returns information about chain tips    |
| getchaintxstats       | Returns transaction statistics          |
| getdifficulty         | Returns the current mining difficulty   |
| getfinalizedblockhash | Returns the hash of the finalized block |

#### Mempool (6 methods)

Methods for querying the memory pool of unconfirmed transactions.

| Method                | Description                                  |
| --------------------- | -------------------------------------------- |
| getmempoolancestors   | Returns mempool ancestors of a transaction   |
| getmempooldescendants | Returns mempool descendants of a transaction |
| getmempoolentry       | Returns mempool data for a transaction       |
| getmempoolinfo        | Returns mempool state information            |
| getrawmempool         | Returns all transaction IDs in mempool       |
| testmempoolaccept     | Tests if transactions would be accepted      |

#### Mining & Network (2 methods)

Methods for mining information and network statistics.

| Method           | Description                         |
| ---------------- | ----------------------------------- |
| getmininginfo    | Returns mining-related information  |
| getnetworkhashps | Returns estimated network hash rate |

#### Transaction (4 methods)

Methods for querying and broadcasting transactions.

| Method             | Description                                    |
| ------------------ | ---------------------------------------------- |
| getrawtransaction  | Returns raw transaction data                   |
| gettxout           | Returns details about an unspent output        |
| gettxoutproof      | Returns proof that a transaction is in a block |
| sendrawtransaction | Broadcasts a raw transaction                   |

#### Utility (7 methods)

Utility methods for address derivation, validation, and node information.

| Method           | Description                           |
| ---------------- | ------------------------------------- |
| deriveaddresses  | Derives addresses from a descriptor   |
| estimatesmartfee | Estimates fee for confirmation target |
| getindexinfo     | Returns index status information      |
| getmemoryinfo    | Returns memory usage information      |
| getrpcinfo       | Returns RPC server information        |
| validateaddress  | Validates a Bitcoin address           |
| verifymessage    | Verifies a signed message             |

### Support

For technical support and questions:

* Support: <support@getblock.io>

### See Also

* [Bitcoin Developer Documentation](https://developer.bitcoin.org/)
* [Bitcoin Core RPC Reference](https://developer.bitcoin.org/reference/rpc/)
* [BIP Repository](https://github.com/bitcoin/bips)


---

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

```
GET https://docs.getblock.io/api-reference/bitcoin-btc.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.

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