# PDFDocument.fromUrlProgressive()

```ts
static fromUrlProgressive(url: string, options?: OpenProgressiveOptions): Promise<PDFDocument>
```

Open over HTTP range requests, before the whole file has arrived: the viewer appears and the first pages become viewable after a small fraction of the file has downloaded, while the rest streams in the background. Works best with linearized ("fast web view") PDFs but benefits any PDF. Requires a server that honors `Range` requests (checked automatically; falls back to a normal full download when it does not).

Until `isFullyLoaded` is true the document is **view-only**: the editing tools are grayed out, and undo snapshots, page management, search and export wait for completion (`whenFullyLoaded()`). Form fields can be filled meanwhile. The document API does not wait: `save()`, `pages.extract()` and every write through its namespaces reject with `INVALID_STATE` until then. Pages scrolled to before their bytes arrive download on demand (`ensurePageAvailable()` — the viewer does this automatically for pages and thumbnails).

- Kind: static method
- Since: 1.0.0

| Parameter | Type | Description |
| --- | --- | --- |
| `url` | `string` | The URL to open over HTTP range requests. |
| `options?` | `OpenProgressiveOptions` | What `fromUrl` takes (every range request carries `headers`, `credentials` and `signal`) plus `chunkSize` (range-request size in bytes, default 256 KiB) and `onProgress` (`(downloaded, total) => void`). |

Returns `Promise<PDFDocument>`

Throws:

- `ABORTED` — the `signal` was aborted.
- `CORS_ERROR` — the server did not allow the page's origin.
- `NETWORK_ERROR` — the request failed, or the progressive download could not finish.
- `NOT_INITIALIZED` — `Kernstra.init()` has not resolved.
- `FORMAT_ERROR` — not a PDF, or a corrupt one.
- `PASSWORD_ERROR` — a password is required, or the one supplied is wrong.
- `SECURITY_ERROR` — encrypted with a security handler the SDK cannot open.
- `LICENSE_REQUIRED` — opened under a stopped license: no document opens.

```ts
const doc = await PDFDocument.fromUrlProgressive('/big-report.pdf', {
  chunkSize: 256 * 1024, // range-request size (default 256 KiB)
  onProgress: (loaded, total) => updateProgressBar(loaded / total),
});
```

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/fromurlprogressive