> For the complete documentation index, see [llms.txt](https://docs.fastnode.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fastnode.io/polkadot-and-substrate/kusama.md).

# Kusama

The Kusama API provides secure, low-latency access to the Kusama network through the Substrate **JSON-RPC** interface — compatible with polkadot.js and other Substrate SDKs. FastNode operates **full** nodes for this network, so you can read on-chain data and submit transactions without running your own infrastructure.

## Endpoints

| Environment | Endpoint                                |
| ----------- | --------------------------------------- |
| Mainnet     | `https://ksm.fastnode.cc/YOUR-API-KEY/` |
| WebSocket   | `wss://ksm.fastnode.cc/YOUR-API-KEY`    |

## Example request

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

```bash
curl --location 'https://ksm.fastnode.cc/YOUR-API-KEY/' \
  --header 'Content-Type: application/json' \
  --data '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "chain_getHeader",
    "params": []
  }'
```

{% endtab %}

{% tab title="Python" %}

```python
import requests

url = "https://ksm.fastnode.cc/YOUR-API-KEY/"
payload = {"jsonrpc": "2.0", "id": 1, "method": "chain_getHeader", "params": []}
print(requests.post(url, json=payload).json())
```

{% endtab %}
{% endtabs %}

**Response**

```json
{ "jsonrpc": "2.0", "id": 1, "result": { "parentHash": "0x…", "number": "0x14e9a2c", "stateRoot": "0x…" } }
```

## Common methods

| Method                    | Description                                            |
| ------------------------- | ------------------------------------------------------ |
| `system_chain`            | Returns the chain name.                                |
| `system_health`           | Returns node health information.                       |
| `chain_getHeader`         | Returns the header of a block (best block by default). |
| `chain_getBlock`          | Returns the full block.                                |
| `chain_getBlockHash`      | Returns the block hash for a block number.             |
| `chain_getFinalizedHead`  | Returns the hash of the last finalized block.          |
| `state_getRuntimeVersion` | Returns the runtime version.                           |
| `state_getStorage`        | Reads a storage entry at a block.                      |
| `author_submitExtrinsic`  | Submits a signed extrinsic.                            |
| `chain_subscribeNewHeads` | WSS subscription: new block headers.                   |

{% hint style="info" %}
The table above lists the most-used methods. For the complete method set, see the [Polkadot JSON-RPC docs](https://wiki.polkadot.network/). All standard methods are supported unless noted otherwise.
{% endhint %}

***

Need higher limits, archive depth, or methods not enabled on the shared plan? Contact **<support@fastnode.io>** or deploy a dedicated node from the dashboard.


---

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