> ## Documentation Index
> Fetch the complete documentation index at: https://orderly.network/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# bbo

> Subscribe to best bid and offer (BBO) updates for a single symbol via WebSocket, pushed every 10ms.

Push interval: 10ms

```json theme={null}
{
  "id": "clientID5",
  "topic": "PERP_WOO_USDC@bbo",
  "event": "subscribe"
}
```

**Parameters**

| Name  | Type   | Required | Description               |
| ----- | ------ | -------- | ------------------------- |
| id    | string | Y        | id generate by client     |
| event | string | Y        | `subscribe`/`unsubscribe` |
| topic | string | Y        | `{symbol}@bbo`            |

<RequestExample>
  ```json Response theme={null}
  {
    "id": "clientID5",
    "event": "subscribe",
    "success": true,
    "ts": 1609924478533
  }
  ```
</RequestExample>

<ResponseExample>
  ```json Subscribed Message theme={null}
  {
    "topic": "PERP_WOO_USDC@bbo",
    "ts": 1614152296945,
    "data": {
      "symbol": "PERP_WOO_USDC",
      "ask": 0.30939,
      "askSize": 4508.53,
      "bid": 0.30776,
      "bidSize": 25246.14
    }
  }
  ```
</ResponseExample>