> For the complete documentation index, see [llms.txt](https://ajaib.gitbook.io/ajaib-exchange-open-api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ajaib.gitbook.io/ajaib-exchange-open-api/websocket-references/web-socket-streams/order-book-ticker.md).

# Order Book Ticker

**Functionality:** To subscribe order book ticker event stream.

**Authentication:** Required

**Stream Name:** \<symbol>@bookTicker

**Update Time:** Real-time

> Note: this WebSocket stream will return data in real-time whenever the top level order book changes.

Response

<table><thead><tr><th width="145">Name</th><th width="210">Type</th><th>Description</th></tr></thead><tbody><tr><td>u</td><td>long</td><td>Websocket update id</td></tr><tr><td>s</td><td>string</td><td>The trading pair symbol. Refer to <a href="https://ajaib.gitbook.io/coin-exchange-open-api/getting-started/quickstart#:~:text=Asset%20Symbols%20/%20Trading%20Pairs">this</a>.</td></tr><tr><td>b</td><td>string</td><td>Best bid's price</td></tr><tr><td>B</td><td>string</td><td>Best bid's quantity</td></tr><tr><td>a</td><td>string</td><td>Best ask's price</td></tr><tr><td>A</td><td>string</td><td>Best ask's quantity</td></tr></tbody></table>

Response Sample

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

```javascript
{
  "u":400900217,
  "s":"BNB_USDT",
  "b":"25.35190000",
  "B":"31.21000000",
  "a":"25.36520000",
  "A":"40.66000000"
}
```

{% endtab %}
{% endtabs %}