# PDFDocument.ensurePageAvailable()

```ts
ensurePageAvailable(pageIndex: number): Promise<void>
```

Only meaningful after `fromUrlProgressive()`. Fetches the ranges that page needs, and resolves when it can be rendered. The viewer does this automatically for pages and thumbnails.

- Kind: method
- Since: 1.0.0

| Parameter | Type | Description |
| --- | --- | --- |
| `pageIndex` | `number` | Zero-based page index. |

Returns `Promise<void>`: Resolves when the page can be rendered.

```ts
if (!doc.isPageReady(9)) await doc.ensurePageAvailable(9);
```

Part of [PDFDocument](https://kernstra.com/docs/web-sdk/api/pdfdocument) in the Kernstra Web SDK 1.0.0 API reference.

Web page: https://kernstra.com/docs/web-sdk/api/pdfdocument/ensurepageavailable